Advanced backhaul services

ABSTRACT

“Tiered” groups of devices (tiered service radios) and/or licenses associated with the devices or users so as to provide a hieratical set of interference protection mechanisms for members of each tier of service are disclosed. Point-to-point and point-to-multipoint data links for any communication application, including wireless backhaul applications, are also disclosed. Exemplary systems, devices, and methods disclosed herein allow for the efficient operation of such a tiered service. Interference protection among tiered service devices belonging to one or more tiers of the service, from other devices within the same tier of service, or devices of other tiers of service, is disclosed. Identification of other devices of the same or differing tiers of service, and interference mitigation between other tiered service devices based upon intercommunication between the devices, and/or via a central registry database, are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/666,294, filed Mar. 23, 2015, currently pending, which is acontinuation of U.S. patent application Ser. No. 14/098,456, filed onDec. 5, 2013, now U.S. Pat. No. 8,989,762, the disclosure of which areincorporated herein by reference in their entirety.

BACKGROUND 1. Field

The present disclosure relates generally to data networking and inparticular to a backhaul radio for connecting remote edge accessnetworks to core networks.

2. Related Art

Data networking traffic has grown at approximately 100% per year forover 20 years and continues to grow at this pace. Only transport overoptical fiber has shown the ability to keep pace with thisever-increasing data networking demand for core data networks. Whiledeployment of optical fiber to an edge of the core data network would beadvantageous from a network performance perspective, it is oftenimpractical to connect all high bandwidth data networking points withoptical fiber at all times. Instead, connections to remote edge accessnetworks from core networks are often achieved with wireless radio,wireless infrared, and/or copper wireline technologies.

Radio, especially in the form of cellular or wireless local area network(WLAN) technologies, is particularly advantageous for supportingmobility of data networking devices. However, cellular base stations orWLAN access points inevitably become very high data bandwidth demandpoints that require continuous connectivity to an optical fiber corenetwork.

When data aggregation points, such as cellular base station sites, WLANaccess points, or other local area network (LAN) gateways, cannot bedirectly connected to a core optical fiber network, then an alternativeconnection, using, for example, wireless radio or copper wirelinetechnologies, must be used. Such connections are commonly referred to as“backhaul.”

Many cellular base stations deployed to date have used copper wirelinebackhaul technologies such as T1, E1, DSL, etc. when optical fiber isnot available at a given site. However, the recent generations of HSPA+and LTE cellular base stations have backhaul requirements of 100 Mb/s ormore, especially when multiple sectors and/or multiple mobile networkoperators per cell site are considered. WLAN access points commonly havesimilar data backhaul requirements. These backhaul requirements cannotbe practically satisfied at ranges of 300 m or more by existing copperwireline technologies. Even if LAN technologies such as Ethernet overmultiple dedicated twisted pair wiring or hybrid fiber/coax technologiessuch as cable modems are considered, it is impractical to backhaul atsuch data rates at these ranges (or at least without adding intermediaterepeater equipment). Moreover, to the extent that such special wiring(i.e., CAT 5/6 or coax) is not presently available at a remote edgeaccess network location; a new high capacity optical fiber isadvantageously installed instead of a new copper connection.

Rather than incur the large initial expense and time delay associatedwith bringing optical fiber to every new location, it has been common tobackhaul cell sites, WLAN hotspots, or LAN gateways from offices,campuses, etc. using microwave radios. An exemplary backhaul connectionusing the microwave radios 132 is shown in FIG. 1. Traditionally, suchmicrowave radios 132 for backhaul have been mounted on high towers 112(or high rooftops of multi-story buildings) as shown in FIG. 1, suchthat each microwave radio 132 has an unobstructed line of sight (LOS)136 to the other. These microwave radios 132 can have data rates of 100Mb/s or higher at unobstructed LOS ranges of 300 m or longer withlatencies of 5 ms or less (to minimize overall network latency).

Traditional microwave backhaul radios 132 operate in a Point-to-point(PTP) configuration using a single “high gain” (typically >30 dBi oreven >40 dBi) antenna at each end of the link 136, such as, for example,antennas constructed using a parabolic dish. Such high gain antennasmitigate the effects of unwanted multipath self-interference or unwantedco-channel interference from other radio systems such that high datarates, long range and low latency can be achieved. These high gainantennas however have narrow radiation patterns.

Furthermore, high gain antennas in traditional microwave backhaul radios132 require very precise, and usually manual, physical alignment oftheir narrow radiation patterns in order to achieve such highperformance results. Such alignment is almost impossible to maintainover extended periods of time unless the two radios have a clearunobstructed line of sight (LOS) between them over the entire range ofseparation. Furthermore, such precise alignment makes it impractical forany one such microwave backhaul radio to communicate effectively withmultiple other radios simultaneously (i.e., a “point-to-multipoint”(PMP) configuration).

In wireless edge access applications, such as cellular or WLAN, advancedprotocols, modulation, encoding and spatial processing across multipleradio antennas have enabled increased data rates and ranges for numeroussimultaneous users compared to analogous systems deployed 5 or 10 yearsago for obstructed LOS propagation environments where multipath andco-channel interference were present. In such systems, “low gain”(usually <6 dBi) antennas are generally used at one or both ends of theradio link both to advantageously exploit multipath signals in theobstructed LOS environment and allow operation in different physicalorientations as would be encountered with mobile devices. Althoughimpressive performance results have been achieved for edge access, suchresults are generally inadequate for emerging backhaul requirements ofdata rates of 100 Mb/s or higher, ranges of 300 m or longer inobstructed LOS conditions, and latencies of 5 ms or less.

In particular, “street level” deployment of cellular base stations, WLANaccess points or LAN gateways (e.g., deployment at street lamps, trafficlights, sides or rooftops of single or low-multiple story buildings)suffers from problems because there are significant obstructions for LOSin urban environments (e.g., tall buildings, or any environments wheretall trees or uneven topography are present).

FIG. 1 illustrates edge access using conventional unobstructed LOS PTPmicrowave radios 132. The scenario depicted in FIG. 1 is common for many2^(nd) Generation (2G) and 3^(rd) Generation (3G) cellular networkdeployments using “macrocells”. In FIG. 1, a Cellular Base TransceiverStation (BTS) 104 is shown housed within a small building 108 adjacentto a large tower 112. The cellular antennas 116 that communicate withvarious cellular subscriber devices 120 are mounted on the towers 112.The PTP microwave radios 132 are mounted on the towers 112 and areconnected to the BTSs 104 via an nT1 interface. As shown in FIG. 1 byline 136, the radios 132 require unobstructed LOS.

The BTS on the right 104 a has either an nT1 copper interface or anoptical fiber interface 124 to connect the BTS 104 a to the Base StationController (BSC) 128. The BSC 128 either is part of or communicates withthe core network of the cellular network operator. The BTS on the left104 b is identical to the BTS on the right 104 a in FIG. 1 except thatthe BTS on the left 104 b has no local wireline nT1 (or optical fiberequivalent) so the nT1 interface is instead connected to a conventionalPTP microwave radio 132 with unobstructed LOS to the tower on the right112 a. The nT1 interfaces for both BTSs 104 a, 104 b can then bebackhauled to the BSC 128 as shown in FIG. 1.

FIG. 2A is a block diagram of the major subsystems of a conventional PTPmicrowave radio 200A for the case of Time-Division Duplex (TDD)operation, and FIG. 2B is a block diagram of the major subsystems of aconventional PTP microwave radio 200B for the case of Frequency-DivisionDuplex (FDD) operation.

As shown in FIG. 2A and FIG. 2B, the conventional PTP microwave radiotraditionally uses one or more (i.e. up to “n”) T1 interfaces 204A and204B (or in Europe, E1 interfaces). These interfaces (204A and 204B) arecommon in remote access systems such as 2G cellular base stations orenterprise voice and/or data switches or edge routers. The T1 interfacesare typically multiplexed and buffered in a bridge (e.g., the InterfaceBridge 208A, 208B) that interfaces with a Media Access Controller (MAC)212A, 212B.

The MAC 212A, 212B is generally denoted as such in reference to asub-layer of Layer 2 within the Open Systems Interconnect (OSI)reference model. Major functions performed by the MAC include theframing, scheduling, prioritizing (or “classifying”), encrypting anderror checking of data sent from one such radio at FIG. 2A or FIG. 2B toanother such radio. The data sent from one radio to another is generallyin a “user plane” if it originates at the T1 interface(s) or in the“control plane” if it originates internally such as from the Radio LinkController (RLC) 248A, 248B shown in FIG. 2A or FIG. 2B.

With reference to FIGS. 2A and 2B, the Modem 216A, 216B typicallyresides within the “baseband” portion of the Physical (PHY) layer 1 ofthe OSI reference model. In conventional PTP radios, the baseband PHY,depicted by Modem 216A, 216B, typically implements scrambling, forwarderror correction encoding, and modulation mapping for a single RFcarrier in the transmit path. In receive, the modem typically performsthe inverse operations of demodulation mapping, decoding anddescrambling. The modulation mapping is conventionally QuadratureAmplitude Modulation (QAM) implemented with In-phase (I) andQuadrature-phase (Q) branches.

The Radio Frequency (RF) 220A, 220B also resides within the PHY layer ofthe radio. In conventional PTP radios, the RF 220A, 220B typicallyincludes a single transmit chain (Tx) 224A, 224B that includes I and Qdigital to analog converters (DACs), a vector modulator, optionalupconverters, a programmable gain amplifier, one or more channelfilters, and one or more combinations of a local oscillator (LO) and afrequency synthesizer. Similarly, the RF 220A, 220B also typicallyincludes a single receive chain (Rx) 228A, 228B that includes I and Qanalog to digital converters (ADCs), one or more combinations of an LOand a frequency synthesizer, one or more channel filters, optionaldownconverters, a vector demodulator and an automatic gain control (AGC)amplifier. Note that in many cases some of the one or more LO andfrequency synthesizer combinations can be shared between the Tx and Rxchains.

As shown in FIGS. 2A and 2B, conventional PTP radios 200A, 200B alsoinclude a single power amplifier (PA) 232A, 232B. The PA 232A, 232Bboosts the transmit signal to a level appropriate for radiation from theantenna in keeping with relevant regulatory restrictions andinstantaneous link conditions. Similarly, such conventional PTP radios232A, 232B typically also include a single low-noise amplifier (LNA)236, 336 as shown in FIGS. 2A and 2B. The LNA 236A, 236B boosts thereceived signal at the antenna while minimizing the effects of noisegenerated within the entire signal path.

As described above, FIG. 2A illustrates a conventional PTP radio 200Afor the case of TDD operation. As shown in FIG. 2A, conventional PTPradios 200A typically connect the antenna 240A to the PA 232A and LNA236A via a band-select filter 244A and a single-pole, single-throw(SPST) switch 242A.

As described above, FIG. 2B illustrates a conventional PTP radio 200Bfor the case of FDD operation. As shown in FIG. 2B, in conventional PTPradios 200B, then antenna 240B is typically connected to the PA 232B andLNA 236B via a duplexer filter 244B. The duplexer filter 244B isessentially two band-select filters (tuned respectively to the Tx and Rxbands) connected at a common point.

In the conventional PTP radios shown in FIGS. 2A and 2B, the antenna240A, 240B is typically of very high gain such as can be achieved by aparabolic dish so that gains of typically >30 dBi (or even sometimes >40dBi), can be realized. Such an antenna usually has a narrow radiationpattern in both the elevation and azimuth directions. The use of such ahighly directive antenna in a conventional PTP radio link withunobstructed LOS propagation conditions ensures that the modem 216A,216B has insignificant impairments at the receiver (antenna 240A, 240B)due to multipath self-interference and further substantially reduces thelikelihood of unwanted co-channel interference due to other nearby radiolinks.

Although not explicitly shown in FIGS. 2A and 2B, the conventional PTPradio may use a single antenna structure with dual antenna feedsarranged such that the two electromagnetic radiation patterns emanatedby such an antenna are nominally orthogonal to each other. An example ofthis arrangement is a parabolic dish. Such an arrangement is usuallycalled dual-polarized and can be achieved either by orthogonal verticaland horizontal polarizations or orthogonal left-hand circular andright-hand circular polarizations.

When duplicate modem blocks, RF blocks, and PA/LNA/switch blocks areprovided in a conventional PTP radio, then connecting each PHY chain toa respective polarization feed of the antenna allows theoretically up totwice the total amount of information to be communicated within a givenchannel bandwidth to the extent that cross-polarizationself-interference can be minimized or cancelled sufficiently. Such asystem is said to employ “dual-polarization” signaling. Such systems maybe referred to as having two “streams” of information, whereas multipleinput multiple output (MIMO) systems utilizing spatial multiplexing mayachieve successful communications using even more than two streams inpractice.

When an additional circuit (not shown) is added to FIG. 2A that canprovide either the RF Tx signal or its anti-phase equivalent to eitherone or both of the two polarization feeds of such an antenna, then“cross-polarization” signaling can be used to effectively expand theconstellation of the modem within any given symbol rate or channelbandwidth. With two polarizations and the choice of RF signal or itsanti-phase, then an additional two information bits per symbol can becommunicated across the link. Theoretically, this can be extended andexpanded to additional phases, representing additional information bits.At the receiver, for example, a circuit (not shown) could detect if thetwo received polarizations are anti-phase with respect to each other, ornot, and then combine appropriately such that the demodulator in themodem block can determine the absolute phase and hence deduce the valuesof the two additional information bits. Cross-polarization signaling hasthe advantage over dual-polarization signaling in that it is generallyless sensitive to cross-polarization self-interference but for highorder constellations such as 64-QAM or 256-QAM, the relative increase inchannel efficiency is smaller.

In the conventional PTP radios shown in FIGS. 2A and 2B, substantiallyall the components are in use at all times when the radio link isoperative. However, many of these components have programmableparameters that can be controlled dynamically during link operation tooptimize throughout and reliability for a given set of potentiallychanging operating conditions. The conventional PTP radios of FIGS. 2Aand 2B control these link parameters via a Radio Link Controller (RLC)248A, 248B. The RLC functionality is also often described as a LinkAdaptation Layer that is typically implemented as a software routineexecuted on a microcontroller within the radio that can access the MAC212A, 212B, Modem 216A, 216B, RF 220A, 220B and/or possibly othercomponents with controllable parameters. The RLC 248A, 248B typicallycan both vary parameters locally within its radio and communicate with apeer RLC at the other end of the conventional PTP radio link via“control frames” sent by the MAC 212A, 212B with an appropriateidentifying field within a MAC Header.

Typical parameters controllable by the RLC 248A, 248B for the Modem216A, 216B of a conventional PTP radio include encoder type, encodingrate, constellation selection and reference symbol scheduling andproportion of any given PHY Protocol Data Unit (PPDU). Typicalparameters controllable by the RLC 248A, 248B for the RF 220A, 220B of aconventional PTP radio include channel frequency, channel bandwidth, andoutput power level. To the extent that a conventional PTP radio employstwo polarization feeds within its single antenna, additional parametersmay also be controlled by the RLC 248A, 248B as self-evident from thedescription above.

In conventional PTP radios, the RLC 248A, 248B decides, usuallyautonomously, to attempt such parameter changes for the link in responseto changing propagation environment characteristics such as, forexample, humidity, rain, snow, or co-channel interference. There areseveral well-known methods for determining that changes in thepropagation environment have occurred such as monitoring the receivesignal strength indicator (RSSI), the number of or relative rate of FCSfailures at the MAC 212A, 212B, and/or the relative value of certaindecoder accuracy metrics. When the RLC 248A, 248B determines thatparameter changes should be attempted, it is necessary in most casesthat any changes at the transmitter end of the link become known to thereceiver end of the link in advance of any such changes. Forconventional PTP radios, and similarly for many other radios, there areat least two well-known techniques which in practice may not be mutuallyexclusive. First, the RLC 248A, 248B may direct the PHY, usually in theModem 216A, 216B relative to FIGS. 2A and 2B, to pre-pend a PHY layerconvergence protocol (PLCP) header to a given PPDU that includes one ormore (or a fragment thereof) given MPDUs wherein such PLCP header hasinformation fields that notify the receiving end of the link ofparameters used at the transmitting end of the link. Second, the RLC248A, 248B may direct the MAC 212A, 212B to send a control frame,usually to a peer RLC 248A, 248B, including various information fieldsthat denote the link adaptation parameters either to be deployed or tobe requested or considered.

The foregoing describes at an overview level the typical structural andoperational features of conventional PTP radios which have been deployedin real-world conditions for many radio links where unobstructed (orsubstantially unobstructed) LOS propagation was possible. Theconventional PTP radio on a whole is completely unsuitable forobstructed LOS PTP or PMP operation.

More recently, as briefly mentioned, there has been significant adoptionof so called multiple input multiple output (MIMO) techniques, whichutilizes spatial multiplexing of multiple information streams between aplurality of transmission antennas to a plurality of receive antennas.The adoption of MIMO has been most beneficial in wireless communicationsystems for use in environments having significant multipath scatteringpropagation. One such system is IEEE802.11n for use in home networking.Attempts have been made to utilize MIMO and spatial multiplexing in lineof sight environments having minimal scattering, which have generallybeen met with failure, in contrast to the use of cross polarizedcommunications. For example IEEE802.11n based Mesh networked nodesdeployed at streetlight elevation in outdoor environments oftenexperience very little benefit from the use of spatial multiplexing dueto the lack of a rich multipath propagation environment. Additionally,many of these deployments have limited range between adjacent mesh nodesdue to physical obstructions resulting in the attenuation of signallevels.

Radios and systems with MIMO capabilities intended for use in both nearline of sight (NLOS) and line of sight (LOS) environments are disclosedin U.S. patent application Ser. No. 13/212,036, now U.S. Pat. No.8,238,318, and Ser. No. 13/536,927, both of which are incorporatedherein by reference, and are referred to herein by the term “IntelligentBackhaul Radio” (IBR).

FIGS. 3A and 3B illustrate exemplary embodiments of the disclosed IBRs.In FIGS. 3A and 3B, the IBRs include interfaces 304A, interface bridge308A, MAC 312A, modem 324A, channel MUX 328A, RF 332A, which includesTx1 . . . TxM 336A and Rx1 . . . RxN 340A, IBR Antenna Array 348A(includes multiple antennas 352A), a Radio Link Controller (RLC) 356Aand a Radio Resource Controller (RRC) 360A. The IBR may optionallyinclude an “Intelligent Backhaul Management System” (or “IBMS”) agent370B as shown in FIG. 3B. It will be appreciated that the components andelements of the IBRs may vary from that illustrated in FIGS. 3A and 3B.

Embodiments of such intelligent backhaul radios, as disclosed in theforegoing references, include one or more demodulator cores within modem324A, wherein each demodulator core demodulates one or more receivesymbol streams to produce a respective receive data interface stream; aplurality of receive RF chains 340A within IBR RF 332A to convert from aplurality of receive RF signals from IBR Antenna Array 348A, to aplurality of respective receive chain output signals; a frequencyselective receive path channel multiplexer within IBR Channelmultiplexer 328A, interposed between the one or more demodulator coresand the plurality of receive RF chains, to produce the one or morereceive symbol streams provided to the one or more demodulator coresfrom the plurality of receive chain output signals; an IBR Antenna Array(348A) including: a plurality of directive gain antenna elements 352A;and one or more selectable RF connections that selectively couplecertain of the plurality of directive gain antenna elements to certainof the plurality of receive RF chains, wherein the number of directivegain antenna elements that can be selectively coupled to receive RFchains exceeds the number of receive RF chains that can accept receiveRF signals from the one or more selectable RF connections; and a radioresource controller, wherein the radio resource controller sets orcauses to be set the specific selective couplings between the certain ofthe plurality of directive gain antenna elements and the certain of theplurality of receive RF chains.

The intelligent backhaul radio may further include one or more modulatorcores within IBR Modem 324A, wherein each modulator core modulates arespective transmit data interface stream to produce one or moretransmit symbol streams; a plurality of transmit RF chains 336A withinIBR RF 332A, to convert from a plurality of transmit chain input signalsto a plurality of respective transmit RF signals; a transmit pathchannel multiplexer within IBR Channel MUX 328A, interposed between theone or more modulator cores and the plurality of transmit RF chains, toproduce the plurality of transmit chain input signals provided to theplurality of transmit RF chains from the one or more transmit symbolstreams; and, wherein the IBR Antenna Array 348A further includes aplurality of RF connections to couple at least certain of the pluralityof directive gain antenna elements to the plurality of transmit RFchains.

The primary responsibility of the RLC 356A in exemplary intelligentbackhaul radios is to set or cause to be set the current transmit“Modulation and Coding Scheme” (or “MCS”) and output power for eachactive link. For links that carry multiple transmit streams and usemultiple transmit chains and/or transmit antennas, the MCS and/or outputpower may be controlled separately for each transmit stream, chain, orantenna. In certain embodiments, the RLC operates based on feedback fromthe target receiver for a particular transmit stream, chain and/orantenna within a particular intelligent backhaul radio.

The intelligent backhaul radio may further include an intelligentbackhaul management system agent 370B that sets or causes to be setcertain policies relevant to the radio resource controller, wherein theintelligent backhaul management system agent exchanges information withother intelligent backhaul management system agents within otherintelligent backhaul radios or with one or more intelligent backhaulmanagement system servers.

FIG. 3C illustrates an exemplary embodiment of an IBR Antenna Array348A. FIG. 3C illustrates an antenna array having Q directive gainantennas 352A (i.e., where the number of antennas is greater than 1). InFIG. 3C, the IBR Antenna Array 348A includes an IBR RF Switch Fabric312C, RF interconnections 304C, a set of Front-ends 308C and thedirective gain antennas 352A. The RF interconnections 304C can be, forexample, circuit board traces and/or coaxial cables. The RFinterconnections 304C connect the IBR RF Switch Fabric 312C and the setof Front-ends 308C. Each Front-end 308C is associated with an individualdirective gain antenna 352A, numbered consecutively from 1 to Q.

FIG. 3D illustrates an exemplary embodiment of the Front-end circuit308C of the IBR Antenna Array 348A of FIG. 3C for the case of TDDoperation, and FIG. 3E illustrates an exemplary embodiment of theFront-end circuit 308C of the IBR Antenna Array 348A of FIG. 3C for thecase of FDD operation. The Front-end circuit 308C of FIG. 3E includes atransmit power amplifier PA 304D, a receive low noise amplifier LNA308D, SPDT switch 312D and band-select filter 316D. The Front-endcircuit 308C of FIG. 3E includes a transmit power amplifier PA 304E,receive low noise amplifier LNA 308E, and duplexer filter 312E. Thesecomponents of the Front-end circuit are substantially conventionalcomponents available in different form factors and performancecapabilities from multiple commercial vendors.

As shown in FIGS. 3D and 3E, each Front-end 308E also includes an“Enable” input 320D, 320E that causes substantially all active circuitryto power-down. Power-down techniques are well known. Power-down isadvantageous for IBRs in which not all of the antennas are utilized atall times. It will be appreciated that alternative embodiments of theIBR Antenna Array may not utilize the “Enable” input 320D, 320E orpower-down feature. Furthermore, for embodiments with antenna arrayswhere some antenna elements are used only for transmit or only forreceive, then certain Front-ends (not shown) may include only thetransmit or only the receive paths of FIGS. 3D and 3E as appropriate.

FIG. 3F illustrates an alternative embodiment of an IBR Antenna Array348A and includes a block diagram of an IBR antenna array according toone embodiment of the invention relating to the use of dedicatedtransmission and reception antennas. In some IBR embodiments theembodiment of FIG. 3C may be replaced with the embodiments described inrelation to FIG. 3F. For instance, such substitution may be made in usewith either FDD, TDD, or even non-conventional duplexing systems. FIG.3F illustrates an antenna array having Q_(R)+Q_(T) directive gainantennas 352A (i.e., where the number of antennas is greater than 1). InFIG. 3F, the IBR Antenna Array 348A includes an IBR RF Switch Fabric312F, RF interconnections 304C, a set of Front-ends 309F and 310F andthe directive gain antennas 352A. The RF interconnections 304C can be,for example, circuit board traces and/or coaxial cables. The RFinterconnections 304C connect the IBR RF Switch Fabric 312F and the setof Front-end Transmission Units 309F and the set of Front-end ReceptionUnits 310F. Each Front-end transmission unit 309F is associated with anindividual directive gain antenna 352A, numbered consecutively from 1 toQ_(T). Each Front-end reception unit 310F is associated with anindividual directive gain antenna 352A, numbered consecutively from 1 toQ_(R). The present embodiment may be used, for example, with the antennaarray embodiments of FIG. 3I, 3J, or embodiments described elsewhere.Such dedicated transmission antennas are coupled to front-endtransmission units 309F and include antenna element 352A.

In alternative embodiment, the IBR RF Switch fabric 312F may be bypassedfor the transmission signals when the number of dedicated transmissionantennas and associated front-end transmission units (Q_(T)) is equal tothe number of RF transmission signals RF-Tx-M (e.g. Q_(T)=M), resultingin directly coupling the IBR RF 336A transmissions to respectivetransmission front-end transmission units 309F. The dedicated receptionantennas, including an antenna element 352A in some embodiments, arecoupled to front-end reception units 310F, which in the presentembodiment are coupled to the IBR RF Switch Fabric. In an additionalalternative embodiment, the IBR RF Switch fabric 312F may be bypassedfor the reception signals when the number of dedicated receptionantennas and associated front-end reception units (Q_(R)) is equal tothe number of RF reception signals RF-Rx-N (e.g. Q_(R)=N), resulting indirectly coupling the IBR RF 340A reception ports to respectivefront-end reception units 310F.

FIG. 3G is a block diagram of a front-end transmission unit according toone embodiment of the invention relating to the use of dedicatedtransmission and reception antennas, and FIG. 3H is a block diagram of afront-end reception unit according to one embodiment of the inventionrelating to the use of dedicated transmission and reception antennas. Asshown in FIGS. 3G and 3H, each Front-end 309F and 310F also includes arespective “Enable” input 325F, 330F that causes substantially allrespective active circuitry to power-down, and any known power-downtechnique may be used. Power-down is advantageous for IBRs in which notall of the antennas are utilized at all times. It will be appreciatedthat alternative embodiments of the IBR Antenna Array may not utilizethe “Enable” input 325F, 330F or any power-down feature. Furthermore,for some embodiments associated with FIG. 3F for example (with antennaarrays where some antenna elements are used only for transmit or onlyfor receive) then certain Front-ends may include only the transmit 309For only the receive paths 310F of FIGS. 3G and 3H as appropriate. Withrespect to FIG. 3G, Bandpass filter 340G receives transmission signalRF-SW-Tx-qt, provides filtering and couples the signal to poweramplifier 304G, then to low pass filter 350G. The output of the lowpassfilter is then coupled to dedicated transmission antenna, which includesdirective antenna element 352A. With respect to FIG. 3H, directiveantenna element 352A is a dedicated receive only antenna and coupled toreceive filter 370H, when is in turn coupled to LNA 308H. The resultingamplified receive signal is coupled to band bass filter 360H, whichprovides output RF-SW-Rx-qr.

As described above, each Front-end (FE-q) corresponds to a particulardirective gain antenna 352A. Each antenna 352A has a directivity gainGq. For IBRs intended for fixed location street-level deployment withobstructed LOS between IBRs, whether in PTP or PMP configurations, eachdirective gain antenna 352A may use only moderate directivity comparedto antennas in conventional PTP systems at a comparable RF transmissionfrequency.

As described in greater detail in U.S. patent application Ser. No.13/212,036, now U.S. Pat. No. 8,238,318, and Ser. No. 13/536,927 andincorporated herein by reference, various antenna configurations may beutilized in point-to-point and point-to-multipoint embodiments of thecurrent invention. With reference to FIG. 3I, a block diagram of anexemplary IBR antenna array is depicted. Such an array may also be usedin part or in entirety as a receive and/or transmit antenna array for anIBR device according to one embodiment of the invention. As the arrayincludes a plurality of antenna panels (310I-A . . . D, 330I, forexample), each panel may include one of the antenna structures orindividual antennas including the antenna structures. In an IBR device,normally two such antenna arrays including some or all of the antennapanels depicted in FIG. 3I would be utilized with an azimuthaldirectional bias different for each array or for each collection of oneor more such antenna panels to optimize link performance between theinstant IBR and the source and destination devices.

While FIG. 3I is a diagram of an exemplary horizontally arrangedintelligent backhaul radio antenna array, FIG. 3J is a diagram of anexemplary vertically arranged intelligent backhaul radio antenna arraythat may also be used in part or in entirety as a receive and/ortransmit antenna array for an IBR device according to one embodiment ofthe invention. The depicted antenna arrays shown in FIGS. 3I and 3J areintended for operation in the 5 to 6 GHz band. Analogous versions of thearrangement shown in FIGS. 3I and 3J are possible for any bands withinthe range of at least 500 MHz to 100 GHz as will be appreciated by thoseof skill in the art of antenna design.

The exemplary transmit directive antenna elements depicted in FIGS. 3Iand 3J include multiple dipole radiators arranged for either dual slant45 degree polarization (FIG. 3I) or dual vertical and horizontalpolarization (FIG. 3J) with elevation array gain as described in greaterdetail in U.S. patent application Ser. No. 13/536,927 and incorporatedherein. In one exemplary embodiment, each transmit directive antennaelement has an azimuthal beam width of approximately 100-120 degrees andan elevation beam width of approximately 15 degrees for a gain Gqt ofapproximately 12 dB.

The receive directive antenna elements depicted in FIGS. 3I and 3Jinclude multiple patch radiators arranged for either dual slant 45degree polarization or dual vertical and horizontal polarization withelevation array gain and azimuthal array gain as described in greaterdetail in U.S. patent application Ser. No. 13/536,927 and incorporatedherein. In one exemplary embodiment, each receive directive antennaelement has an azimuthal beam width of approximately 40 degrees and anelevation beam width of approximately 15 degrees for a gain Gqr ofapproximately 16 dB.

Preliminary measurements of exemplary antenna arrays similar to thosedepicted in FIG. 3I show isolation of approximately 40 to 50 dB betweenindividual transmit directive antenna elements and individual receivedirective antenna elements of same polarization with an exemplarycircuit board and metallic case behind the radiating elements and aplastic ray dome in front of the radiating elements. Analogouspreliminary measurements of exemplary antenna arrays similar to thosedepicted in FIG. 3J show possible isolation improvements of up to 10 to20 dB for similar directive gain elements relative to FIG. 3I.

Other directive antenna element types are also known to those of skillin the art of antenna design including certain types described ingreater detail in U.S. patent application Ser. No. 13/536,927 andincorporated herein.

In the exemplary IBR Antenna Array 348A illustrated in FIG. 3A throughFIG. 3J, the total number of individual antenna elements 352A, Q, isgreater than or equal to the larger of the number of RF transmit chains336A, M, and the number of RF receive chains 340A, N. In someembodiments, some or all of the antennas 352A may be split into pairs ofpolarization diverse antenna elements realized by either two separatefeeds to a nominally single radiating element or by a pair of separateorthogonally oriented radiating elements. Such cross polarizationantenna pairs enable either increased channel efficiency or enhancedsignal diversity as described for the conventional PTP radio. Thecross-polarization antenna pairs as well as any non-polarized antennasare also spatially diverse with respect to each other. Additionally, theindividual antenna elements may also be oriented in different directionsto provide further channel propagation path diversity.

The foregoing discussion related to intelligent backhaul radios andrelate diagrams have include the use of frequency division duplexing(FDD) and time division duplexing (TDD) techniques and architectures.Such architectures, as discussed, include support of both single inputand single output (SISO) supporting single stream operation, andmultiple input/multiple output (MIMO) multiple stream operation support.Additional embodiments supporting SISO and MIMO technology in specificembodiments include the use so-called zero division duplexed (ZDD)intelligent backhaul radios (ZDD-IBR), as disclosed in U.S. patentapplication Ser. No. 13/609,156, now U.S. Pat. No. 8,422,540, which isadditionally incorporated herein by reference.

Embodiments of the ZDD systems provide for the operation of a IBRwherein the ZDD-IBR transmitter and receiver frequencies are close infrequency to each other so as to make the use of frequency divisionduplexing, as known in the art, impractical. Arrangements of ZDDoperation disclosed in the foregoing referenced application includeso-called “co-channel” embodiments wherein the transmit frequencychannels in use by a ZDD-IBR, and the receive frequencies are partiallyor entirely overlapped in the frequency spectrum. Additionally disclosedembodiments of ZDD-IBRs include so-called “co-band” ZDD operationwherein the channels of operation of the ZDD-IBR are not directlyoverlapped with the ZDD-IBR receive channels of operation, but are closeenough to each other so as to limit the performance the system. Forexample, at specific receiver and transmitter frequency channelseparation, the frequency selectivity of the channel selection filtersin an IBR transmitter and receiver chains may be insufficient to isolatethe receiver(s) from the transmitter signal(s) or associated noise anddistortion, resulting in significant de-sensitization of the IBR'sreceiver(s) performance at specific desired transmit power levels, without the use of disclosed ZDD techniques. Embodiments of the disclosedZDD-IBRs include the use of radio frequency, intermediate frequency andbase band cancelation of reference transmitter and interference signalsfrom the ZDD-IBR receivers in a MIMO configuration. Such disclosed ZDDtechniques utilize the estimation of the channels from the plurality ofIBR transmitters to the plurality of IBR receivers of the sameintelligent backhaul radio, and the adaptive filtering of the referencesignals based upon the channel estimates so as to allow the cancelationthe transmitter signals from the receivers utilizing such estimatedcancelation signals. Such ZDD techniques allow for increased isolationbetween the desired receive signals and the ZDD-IBR's transmitters invarious embodiments including MIMO (and SISO) configurations.

The support for MIMO operation (FDD, TDD, or ZDD) is highly dependentupon the radio propagation environment between the two radios incommunication with each other. The following discussion provides for ageneral discussion relating to the MIMO channel, and will provide abasis for further discussion. Referring now to FIG. 3K-A the MIMOchannel matrix is depicted. Transceiver MIMO Station 3K-05 is incommunication with MIMO Station 3K-10 utilizing MIMO channel matrix (Eq.3K-1) of FIG. 3K-B between the 2 stations of FIG. 3K-A. In an example ofa two-by-two MIMO system, two spatial streams are utilized between thetwo MIMO stations. The channel propagation matrix of Eq. 3K-1 is oforder M by N (M rows and N columns). A particular element of the channelpropagation matrix, h_(mn), represents the frequency response of thewireless channel from the n^(th) transmitter to the m^(th) receiver.Therefore each element of the channel propagation matrix H has anindividual complex number, if the channel is “frequency flat,” or acomplex function of frequency, if the channel is “frequency selective,”which represents the amplitude and phase of the propagation channelbetween one transmitter and one receiver of MIMO Stations 3K-05 and3K-10. Often, the channel propagation matrix and the individualpropagation coefficients are frequency selective, meaning that thecomplex value of the coefficients vary as a function of frequency asmentioned. In a rich, multipath scattering environment, as depicted inFIG. 3L, in which sufficient signal strength reaches an intendedreceiver but is scattered amongst the various structures between aparticular MIMO transmitter and MIMO receiver, the spatial distributionof the arriving signals is referred to as a rich multipath environmentin which there is a significant angular scattering among the receivingsignals at the intended receiver.

In order to separate the MIMO streams received at an intended receiver,such as MIMO Station 3K-05 or MIMO Station 3K-10, the channelpropagation matrix H must be determined, as known in the art. Theprocess of determining the channel propagation matrix is often performedutilizing pilot channels, preambles, and/or symbols or other knownreference information. Examples of prior art systems utilizing suchtechniques include IEEE 802.11n, LTE, or HSPA, as well as variousembodiments of intelligent backhaul radios per U.S. Pat. Nos. 8,238,818,8,422,540 and U.S. patent application Ser. No. 13/536,927 asincorporated in their entireties herein.

In order for MIMO systems (including the foregoing mentioned MIMOsystems) to support a plurality of spatial MIMO streams, the order ofthe propagation matrix (referenced as Eq. 3K-1) must equal or exceed thedesired number of streams. While this condition is necessary, it is notsufficient. The rank of the matrix must also equal or exceed the numberof desired spatial streams. The rank of a matrix is the maximum numberof linearly independent column vectors of the propagation matrix. Suchterminology is known in the art with respect to linear algebra. Thenumber of supportable MIMO streams must be less than or equal to therank of the channel propagation matrix. When the propagationcoefficients from multiple transmitters of a MIMO station to a pluralityof intended receive antennas are correlated, the number of linearlyindependent column vectors of the channel propagation matrix H isreduced and consequently the system will support fewer MIMO streams.Such a condition often occurs in environments where a small angularspread at the desired intended receiver is present, such as is the casewith a line-of-sight environment where the two MIMO stations are asignificant distance apart, such that the angular resolution of thereceiving antennas at MIMO Station 3K-10 is insufficient to resolve andseparate the signals transmitted from the plurality of transmitters atMIMO Station 3K-05. Such a condition is referred to as anill-conditioned channel matrix for the desired number of streams in theMIMO system, due to the rank of the channel propagation matrix (i.e. thenumber of linearly independent column vectors) being less than thedesired number of MIMO streams between the two MIMO stations. Thereasoning behind the rank of the channel propagation matrix beingrequired to be greater than or equal to the desired number of MIMOstreams is related to how the individual streams are separated from oneanother at the intended receiving MIMO station. As is known in the art,the MIMO performance is quite sensitive to the invertability of thechannel propagation matrix. Such invertability, as previously mentioned,may be compromised by the receiving antenna correlation, which may becaused by close antenna spacing or small angular spread at the intendedMIMO receiver. The line-of-sight condition between two MIMO stations mayresult in such a small angular spread between the MIMO receivers,resulting in the channel matrix being noninvertible or degenerate.Multipath fading, which often results from large angular spreads amongstindividual propagation proponents between two antennas, enriches thecondition of the channel propagation matrix, making the individualcolumn vectors linearly independent and allowing the channel propagationmatrix to be invertible. The inversion of the channel propagation matrixresults in weights (vectors), which are utilized with the desiredreceive signals to separate the linear combination of transmittedstreams into individual orthogonal streams, allowing for properreception of each individual stream from spatially multiplexed compositeinformation streams. In a line-of-sight environment, all of the columnvectors of the channel propagation matrix H may be highly correlated,resulting in a matrix rank of 1 or very close to 1. Such a matrix isnoninvertible and ill-conditioned, resulting in the inability to supportspatial multiplexing and additional streams (other than by the use ofpolarization multiplexing, which provides for only 2 streams asdiscussed).

FIG. 3L illustrates an exemplary deployment of intelligent backhaulradios (IBRs). As shown in FIG. 3L, the IBRs 300L are deployable atstreet level with obstructions such as trees 303L, hills 308L, buildings312L, etc. between them. Embodiments of intelligent backhaul radios(IBRs) are discussed in co-pending US patent application Ser. No.13/212,036, now U.S. Pat. No. 8,238,318, and Ser. No. 13/536,927, theentire contents of which is incorporated herein. The IBRs 300L are alsodeployable in configurations that include point-to-multipoint (PMP), asshown in FIG. 3L, as well as point-to-point (PTP). In other words, eachIBR 300L may communicate with more than one other IBR 300L.

For 3G and especially for 4^(th) Generation (4G), cellular networkinfrastructure is more commonly deployed using “microcells” or“picocells.” In this cellular network infrastructure, compact basestations (eNodeBs) 316L are situated outdoors at street level. When sucheNodeBs 316L are unable to connect locally to optical fiber or a copperwireline of sufficient data bandwidth, then a wireless connection to afiber “point of presence” (POP) requires obstructed LOS capabilities, asdescribed herein.

For example, as shown in FIG. 3L, the IBRs 300L include an AggregationEnd IBR (AE-IBR) and Remote End IBRs (RE-IBRs). The eNodeB 316L of theAE-IBR is typically connected locally to the core network via a fiberPOP 320L. The RE-IBRs and their associated eNodeBs 316L are typicallynot connected to the core network via a wireline connection; instead,the RE-IBRs are wirelessly connected to the core network via the AE-IBR.As shown in FIG. 3L, the wireless connection between the IBRs includeobstructions (i.e., there may be an obstructed LOS connection betweenthe RE-IBRs and the AE-IBR). Note that the Tall Building 312Lsubstantially impedes the signal transmitted from RE-IBR 300L to AR-IBR300L. Additionally, in at least one example scenario, the tree (303L)provides unacceptable signal attenuation between an RE-IBR 300L and theAE-IBR 300L.

As discussed above, the advances in cellular communications, and morespecifically the Third Generation Partnership Program's (3GPP,www.3GPP.org) Long Term Evolution (LTE), and associated cellular “offload” use of IEEE 802.11 communication protocols continues to drive thedata backhaul requirements of cellular infrastructure sites to everincreasing levels. The need for an increasing number of wirelessbackhaul links to satisfy the cellular backhaul demand demands the useof potentially congested wireless spectrum resources.

The Federal Communications Commission (FCC) has allowed for the use ofcurrently licensed broadcast television spectrum for use by unlicenseddevices. This program has been commonly referred to as the “TVWhitespaces” reuse (http://www.fcc.gov/topic/white-space). A detaileddescription of the program is provided in FCC order FCC-10-174A1, andthe rules for unlicensed devices that operate in the TV bands are setforth in 47 C.F.R. §§ 15.701-.717. See TITLE 47—Telecommunication;CHAPTER I—FEDERAL COMMUNICATIONS COMMISSION; SUBCHAPTER A—GENERAL, PART15—RADIO FREQUENCY DEVICES, Subpart H—TELEVISION BAND DEVICES(http://www.ecfr.gov/cgi-bin/text-idx?c=ecfr&SID=30f46f0753577b10de41d650c7ad1941&rgn=div6&view=text&node=47:1.0.1.1.16.8&idno=47).

The TV Whitespaces program provides for a reuse of underutilizedspectrum resources for public use by unlicensed devices (TV BandDevices). Further, so-called “Incumbent Services” remain protected frominterference from the TV Band Devices (TVBDs) by a set of operatingrules and concepts including (selectively extracted from CFR 47 § 15.703Definitions):

-   -   (a) Available channel. A six-megahertz television channel, which        is not being used by an authorized service at or near the same        geographic location as the TVBD and is acceptable for use by an        unlicensed device under the provisions of this subpart.    -   (b) Contact verification signal. An encoded signal broadcast by        a fixed or Mode II device for reception by Mode I devices to        which the fixed or Mode II device has provided a list of        available channels for operation. Such signal is for the purpose        of establishing that the Mode I device is still within the        reception range of the fixed or Mode II device for purposes of        validating the list of available channels used by the Mode I        device and shall be encoded to ensure that the signal originates        from the device that provided the list of available channels. A        Mode I device may respond only to a contact verification signal        from the fixed or Mode II device that provided the list of        available channels on which it operates. A fixed or Mode II        device shall provide the information needed by a Mode I device        to decode the contact verification signal at the same time it        provides the list of available channels.    -   (c) Fixed device. A TVBD that transmits and/or receives        radiocommunication signals at a specified fixed location. A        fixed TVBD may select channels for operation itself from a list        of available channels provided by a TV bands database, initiate        and operate a network by sending enabling signals to one or more        fixed TVBDs and/or personal/portable TVBDs. Fixed devices may        provide to a Mode I personal/portable device a list of available        channels on which the Mode I device may operate under the rules,        including available channels above 512 MHz (above TV channel 20)        on which the fixed TVBD also may operate and a supplemental list        of available channels above 512 MHz (above TV channel 20) that        are adjacent to occupied TV channels on which the Mode I device,        but not the fixed device, may operate.    -   (d) Geo-location capability. The capability of a TVBD to        determine its geographic coordinates within the level of        accuracy specified in § 15.711(b)(1), i.e. 50 meters. This        capability is used with a TV bands database approved by the FCC        to determine the availability of TV channels at a TVBD's        location.    -   (e) Mode I personal/portable device. A personal/portable TVBD        that does not use an internal geo-location capability and access        to a TV bands database to obtain a list of available channels. A        Mode I device must obtain a list of available channels on which        it may operate from either a fixed TVBD or Mode II        personal/portable TVBD. A Mode I device may not initiate a        network of fixed and/or personal/portable TVBDs nor may it        provide a list of available channels to another Mode I device        for operation by such device.    -   (f) Mode II personal/portable device. A personal/portable TVBD        that uses an internal geo-location capability and access to a TV        bands database, either through a direct connection to the        Internet or through an indirect connection to the Internet by        way of fixed TVBD or another Mode II TVBD, to obtain a list of        available channels. A Mode II device may select a channel itself        and initiate and operate as part of a network of TVBDs,        transmitting to and receiving from one or more fixed TVBDs or        personal/portable TVBDs. A Mode II personal/portable device may        provide its list of available channels to a Mode I        personal/portable device for operation on by the Mode I device.    -   (g) Network initiation. The process by which a fixed or Mode II        TVBD sends control signals to one or more fixed TVBDs or        personal/portable TVBDs and allows them to begin communications.    -   (h) Operating channel. An available channel used by a TVBD for        transmission and/or reception.    -   (i) Personal/portable device. A TVBD that transmits and/or        receives radiocommunication signals at unspecified locations        that may change. Personal/portable devices may only transmit on        available channels in the frequency bands 512-608 MHz (TV        channels 21-36) and 614-698 MHz (TV channels 38-51).    -   (j) Receive site. The location where the signal of a full        service television station is received for rebroadcast by a        television translator or low power TV station, including a Class        A TV station, or for distribution by a Multiple Video Program        Distributor (MVPD) as defined in 47 U.S.C. 602(13).    -   (k) Sensing only device. A personal/portable TVBD that uses        spectrum sensing to determine a list of available channels.        Sensing only devices may transmit on any available channels in        the frequency bands 512-608 MHz (TV channels 21-36) and 614-698        MHz (TV channels 38-51).    -   (l) Spectrum sensing. A process whereby a TVBD monitors a        television channel to detect whether the channel is occupied by        a radio signal or signals from authorized services.    -   (m) Television band device (TVBD). Intentional radiators that        operate on an unlicensed basis on available channels in the        broadcast television frequency bands at 54-60 MHz (TV channel        2), 76-88 MHz (TV channels 5 and 6), 174-216 MHz (TV channels        7-13), 470-608 MHz (TV channels 14-36) and 614-698 MHz (TV        channels 38-51).    -   (n) TV bands database. A database system that maintains records        of all authorized services in the TV frequency bands, is capable        of determining the available channels as a specific geographic        location and provides lists of available channels to TVBDs that        have been certified under the Commission's equipment        authorization procedures. TV bands databases that provide lists        of available channels to TVBDs must receive approval by the        Commission.

Under the white spaces rules, TVBDs (other than TVBDs that rely onspectrum sensing) have the requirement of registering with the TV bandsdatabase, and determining available channels of operation. This processrequires providing the database the FCC ID, serial number, geographiclocation, and other information to the database, to receive a list ofavailable channels for operation. TVBDs are further required toperiodically re-register with the database to re-determine availablechannels of operation. An example of a database entry information for aFixed TVDB is provided within CFR 47 § 15.713 TV bands database (f)Fixed TVBD registration (extraction follows).

-   -   (1) Prior to operating for the first time or after changing        location, a fixed TVBD must register with the TV bands database        by providing the information listed in paragraph (f)(3) of this        section.    -   (2) The party responsible for a fixed TVBD must ensure that the        TVBD registration database has the most current, up-to-date        information for that device.    -   (3) The TVBD registration database shall contain the following        information for fixed TVBDs:        -   (i) FCC identifier (FCC ID) of the device;        -   (ii) Manufacturer's serial number of the device;        -   (iii) Device's geographic coordinates (latitude and            longitude (NAD 83) accurate to ±/−50 m);        -   (iv) Device's antenna height above ground level (meters);        -   (v) Name of the individual or business that owns the device;        -   (vi) Name of a contact person responsible for the device's            operation;        -   (vii) Address for the contact person;        -   (viii) E-mail address for the contact person;        -   (ix) Phone number for the contact person.

The foregoing is intended to provide a brief overview of the conceptsand rules associated with the TV White spaces device operation.

While suitable for use by some wireless applications, such a system isnot ideal for use in many highly reliable wireless backhaulapplications. As one example, the lack of protection from interferencefor TVBD registered devices is a significant impediment for achieving ahighly reliable data link for backhaul applications in view ofinterference from unlicensed or other wireless devices, including otherTVBD devices. As another example, there is no approach for devices toarbitrate interference amongst one another. There are significant numberof other deficiencies of the TV white spaces rules making them non-idealfor use in other bands, and in other applications of use such ascellular backhaul.

SUMMARY

The following summary of the invention is included in order to provide abasic understanding of some aspects and features of the invention. Thissummary is not an extensive overview of the invention and as such it isnot intended to particularly identify key or critical elements of theinvention or to delineate the scope of the invention. Its sole purposeis to present some concepts of the invention in a simplified form as aprelude to the more detailed description that is presented below.

Various embodiments of the present invention provide for incorporationof a “Tiered” group of devices and/or licenses associated with providinga hierarchical set of interference protection mechanisms for members ofeach tier of service in a wireless backhaul (or other) application.Exemplary systems, devices, and methods are disclosed in variousembodiments to allow for the efficient operation of such a tieredservice. As previously described, the TV Whitespaces rules do notprovide for mechanisms or devices allowing for such an efficient tieredservice. Embodiments of the invention provide a tiered service whichallows for interference protection among devices belonging to one ormore tiers of the service, from other devices within the same tier ofservice, or other tiers of service. Embodiments of the invention includemechanisms, apparatus, and methods that provide for the identificationof other devices of the same or differing tier of service, and mitigateinterference to or from the device based upon intercommunication betweenthe devices, and/or via a central registry database.

According to other aspects of the invention, a first tiered serviceradio is disclosed for operating in a radio frequency band according torules for operation allowing for radios of multiple tiers of service,including a plurality of receive RF chains; one or more transmit RFchains; an antenna array having a plurality of directive gain antennaelements, wherein each directive gain antenna element is couplable to atleast one receive RF or transmit RF chain; and an interface bridgeconfigured to couple the radio to a data network; wherein the tieredservice radio is configured to perform each of the following:communicate with a network based registry to determine registryinformation associated with any registered radios meeting specificcriteria, wherein the specific criteria includes at least informationassociated with at least higher priority tiered service radio devices tothat of the first tiered service radio; scan one or more radio frequencychannels for the presence of signature radio signals transmitted fromone or more other tiered service radios to generate scan data, andwherein the radio includes at least one adjustable network parameterthat is adjustable based on the scan data, wherein said scanned one ormore radio frequency channels are selected based upon said registryinformation, and wherein the at least one network parameter is adjustedto reduce a potential of interference of the first tiered service radiowith both the other tiered service radios or said registered radios,wherein the adjusting the at least one network parameter includes one ormore of: selecting a frequency channel utilized between the first tieredservice radio and a second tiered service radio; adjusting the effectiveradiation pattern of the first tiered service radio; selecting one ormore of the plurality of directive gain antenna elements; and adjustingthe physical configuration or arrangement of the one or more of theplurality of directive gain antenna elements.

In some embodiments, the tiered service radio is further configured togenerate a scan report based on the scan data and transmit the scanreport to a server.

In some embodiments, the signals include a signal licensed by theFederal Communications Commission (FCC) under service having at leastthree tiers of service, wherein said tiers include at least legacy pointto point backhaul devices at the highest tier and listed in saidregistry, registered and licensed devices at a second tier, andunlicensed and registered devices at a third and lower tier.

In some embodiments, the adjusting the effective radiation patternincludes one or more of: steering the effective radiation pattern inelevation; and steering the effective radiation pattern in azimuth.

In some embodiments, the adjusting the effective radiation patternincludes: calculating digital beam former weights based upon at leastone constraint related to the potential of interference; and applyingthe digital beam former weights.

In some embodiments, the constraint is selected from the groupconsisting of: properties related to or derived from said scan result; adirection in which signal transmission is to be limited; parameterswhich reduce the potential for interfering with one or more of saidregistered radios meeting said specific criteria; parameters whichincrease the likelihood of said first and said second tiered serviceradios meeting performance goals with respect to an interposed wirelesscommunication link; a restriction of use of specific transceivers orspecific antennas of a plurality of transceivers or antennas; a use ofspecific polarizations for transmission; attributes of a collectivetransmission radiation pattern associated with a plurality oftransmitters; a frequency or geometric translation of beam formingweights between receiver weights and transmitter weights; a change inantennas used or selected; a change in operating frequency; andcombinations thereof. In some embodiments, the scan report includes onemore selected from the group consisting of: the location of said firsttiered service radio; the latitude and longitudinal coordinates of oneor more tiered service radios; configuration information related to thefirst tiered service radio; capability information related to the firsttiered service radio; a transmission power capability of said firsttiered service radio; operating frequency capability of said firsttiered service radio; antenna property information related to one ormore antenna for use in reception or transmission by said first tieredservice radio; received signal parameters or demodulated informationfrom another tiered service radio; received signal parameters from atiered service radio; and combinations thereof.

In some embodiments, the tiered service radio is further configured toassess performance after adjustment of the at least one adjustablenetwork parameter.

In some embodiments, the performance of said first tiered service radiois assessed by one or more selected from the group consisting of:performing additional scans; performing additional scans with specificsearch criteria; performing additional scans with limitations infrequency, azimuth, elevation, or time; performing additional scans witha modified antenna selection configuration; performing additional scansusing antennas intended for transmission during normal operation forreception during the additional scanning process; performingtransmission of a signal from the first tiered service radio to thesecond tiered service radio; receiving a signal from the second tieredservice radio by the first tiered service radio.

In some embodiments, the first tiered service radio is configured toalign the antenna array with the second tiered service radio prior tothe scan based on at least one criterion.

In some embodiments, the at least one criterion is based at least inpart upon a signal transmitted from the second tiered service radio.

In some embodiments, the at least one criterion includes a GPS locationand a compass direction.

In some embodiments, the specific criteria includes a geographic region.

In some embodiments, the specific criteria includes a tier of service ofthe first tiered service radio.

In some embodiments, the specific criteria includes a date on whichservice commenced for any tiered service radio registered in theregistry.

In some embodiments, at least one of said signature radio signalstransmitted from the one or more tiered service radios are transmittedinline with information symbols in time from at least one of the tieredservice radios.

In some embodiments, at least one of said signature radio signalstransmitted from the one or more tiered service radios are transmittedas a spread spectrum signal embedded within and simultaneously withinformation symbols in time from at least one of the tiered serviceradios.

In some embodiments, the first tiered service radio transmits asignature radio signal as a first signature during operation with secondtiered service radios.

In some embodiments, the first signature is transmitted inline withinformation symbols in time.

In some embodiments, the first signature is transmitted as a spreadspectrum signal embedded within and simultaneously with informationsymbols.

In some embodiments, the transmitted first signature is transmitted withprogressively increasing interference potential for a period of timeprior to initiation of full operation between the first and secondtiered service radios.

In some embodiments, the progressively increasing interference includestransmission at a power level with an increasing duty cycle oversuccessive periods of time.

In some embodiments, the progressively increasing interference includestransmission at several increasing power levels over successive periodsof time.

In some embodiments, the first tiered service radio alters said at leastone network parameter based upon detecting information within saidregistry or otherwise receiving information informing of detectedinterference related to the transmitted first signature.

In some embodiments, one or more of said other tiered service radios isrespectively also one or more of the registered radios meeting thespecific criteria.

In some embodiments, the scan data includes one or more of thefollowing: information derived form the reception of signature radiosignals; information derived from the reception of signals transmittedfrom said other tiered service radios; information derived from radiosother than tiered service radios; received signal strength information;channel propagation information; tiered service radio identityinformation; angle of arrival of signal information; received signalstrength information, interference information; path loss information;and signal transmission periodicity information.

In some embodiments, said registered radios include devices of the samepriority as the first tiered service radio.

In some embodiments, the registered radios include devices of lesserpriority as the first tiered service radio.

In some embodiments, the registered radios include devices of any tieror any priority as the first tiered service radio.

In some embodiments, the specific criterion additionally includesdevices of the same priority as the first tiered service radio.

In some embodiments, the specific criterion additionally includesdevices of lesser priority as the first tiered service radio.

In some embodiments, the specific criterion additionally includesdevices of any tier or any priority as the first tiered service radio.

In some embodiments, the scan is performed including a common controlchannel, said common control channel being a defined channel forsignature radio signal transmission and reception commonly known to agroup of tiered service radios upon interaction with the registry.

In some embodiments, said specific search criteria includes one or moreof the following: information derived form the reception of signatureradio signals, information derived from the reception of signalstransmitted from said other tiered service radios, information derivedfrom radios other than tiered service radios, received signal strengthinformation, channel propagation information, tiered service radioidentity information, angle of arrival of signal information, receivedsignal strength information, interference information, path lossinformation, and signal transmission periodicity information.

Additional embodiments of the current invention, together with theforgoing embodiments, or individually include the use of AdvancedBackhaul Services (ABS) devices with point-to-point andpoint-to-multipoint radios, such as an IBR, as disclosed in U.S. patentapplication Ser. No. 13/212,036, now U.S. Pat. No. 8,238,318, and Ser.No. 13/536,927, the entireties of which are hereby incorporated byreference. Additionally, further embodiments individually, or incombination with forgoing embodiments include the use of ABS deviceswith so-called zero division duplexed (ZDD) intelligent backhaul radios(ZDD-IBR), as disclosed in U.S. patent application Ser. No. 13/609,156,now U.S. Pat. No. 8,422,540, the entirety of which is herebyincorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated into and constitute apart of this specification, illustrate one or more examples ofembodiments and, together with the description of example embodiments,serve to explain the principles and implementations of the embodiments.

FIG. 1 is an illustration of conventional point-to-point (PTP) radiosdeployed for cellular base station backhaul with unobstructed line ofsight (LOS).

FIG. 2A is a block diagram of a conventional PTP radio for Time DivisionDuplex (TDD).

FIG. 2B is a block diagram of a conventional PTP radio for FrequencyDivision Duplex (FDD).

FIG. 3A is an exemplary block diagram of an IBR.

FIG. 3B is an alternative exemplary block diagram of an IBR.

FIG. 3C is an exemplary block diagram of an IBR antenna array.

FIG. 3D is an exemplary block diagram of a front-end unit for TDDoperation of an IBR.

FIG. 3E is an exemplary block diagram of a front-end unit for FDDoperation of an IBR.

FIG. 3F is an alternative exemplary block diagram of an IBR antennaarray.

FIG. 3G is a block diagram of a front-end transmission unit according toone embodiment of the invention.

FIG. 3H is a block diagram of a front-end reception unit according toone embodiment of the invention.

FIG. 3I is a diagram of an alternative view of an exemplary horizontallyarranged intelligent backhaul radio antenna array according to oneembodiment of the invention.

FIG. 3J is a diagram of an alternative view of an exemplary verticallyarranged intelligent backhaul radio antenna array according to oneembodiment of the invention.

FIG. 3K-A is an illustration of the MIMO station propagation matrixelements.

FIG. 3K-B illustrates the MIMO channel propagation matrix equation andassociated terminology.

FIG. 3L is an exemplary illustration of intelligent backhaul radios(IBRs) deployed for cellular base station backhaul with obstructed LOS.

FIG. 4A is a table of a partial listing for the frequency availabilityfor specific radio services 47 C.F.R. § 101.101, and a proposed new bandof operation for Advanced Backhaul Services.

FIG. 4B illustrates an exemplary deployment for occupancy of services inthe 7125 to 8500 MHZ frequency band for legacy radios and AdvancedBackhaul Services (ABS) compliant radios amongst other services.

FIG. 4C illustrates an exemplary embodiment of Advanced Backhaul Servicetiered service radio interconnection with an exemplary ABS deviceregistry database.

FIG. 4D illustrates an exemplary deployment of an embodiment of AdvancedBackhaul Services tiered service radios within an exemplary geographicregion.

FIG. 4E illustrates exemplary embodiment of a deployment of intelligentbackhaul radios (IBRs) is deployed for cellular base station backhaulwith obstructed LOS in the presence of Tier 1 Incumbent radios accordingto an embodiment of ABS services.

FIG. 4F illustrates an alternative exemplary embodiment of a deploymentof intelligent backhaul radios (IBRs) deployed for cellular base stationbackhaul with obstructed LOS in the presence of Tier 1 Incumbent radiosaccording to an embodiment of ABS services.

FIG. 4G illustrates an exemplary deployment of an intelligent backhaulsystem (IBS) in the presence of an existing exemplary deployment of Tier1 incumbent radios according to one embodiment of the invention.

FIG. 4H illustrates a normalized antenna gain relative to an angle frombore utilizing an exemplary antenna system.

FIG. 5A is an exemplary block diagram of an IBR including a SignatureLink Processor (SLP).

FIG. 5B is an exemplary block diagram of a Signature Link Processor(SLP).

FIG. 5C is an exemplary block diagram of a signature control channelmodem.

FIG. 5D is an illustration of an exemplary Advanced Backhaul Services(ABS) compliant signal including an in-band and inline signature signaldeployed within a single channel.

FIG. 5E is an illustration of an exemplary Advanced Backhaul Services(ABS) compliant signal including an in-band and inline signature signaldeployed within a multiple channels.

FIG. 5F is an illustration of exemplary embodiments of Advanced BackhaulServices (ABS) signature signals of various structure.

FIG. 5G is an illustration of an exemplary Advanced Backhaul Services(ABS) compliant signal including an in-band and embedded signaturesignal.

FIG. 5H is an exemplary block diagram of an embodiment of a SlidingCorrelator (SC).

FIG. 5I is an exemplary block diagram of an embodiment of a ComplexSliding Correlator Block (CSCB).

FIG. 5J is an exemplary block diagram of an embodiment of a SlidingDetector (SD).

FIG. 5K is an exemplary block diagram of an embodiment of an inbandinline signature detector.

FIG. 5L is an exemplary block diagram of an embodiment of an inbandembedded signature detector.

FIG. 6A is an illustration an exemplary Advanced Backhaul Serviceslayered control link communication protocol stack.

FIG. 6B is an exemplary block diagram of an embodiment of an AdvancedBackhaul Services control link protocol processor

FIG. 6C is a flow diagram of the MAC receive process for an AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention.

FIG. 6D is a flow diagram of the MAC transmit process for an AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention.

FIG. 6E is an illustration of the radio link protocol (RLP) messageformat of Advanced Backhaul Services control link control link accordingto one embodiment of the invention.

FIG. 7A is a flow diagram of the RRC transmit process for an AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention.

FIG. 7B is a flow diagram of the RRC scan process for an AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention.

FIG. 7C is a flow diagram of the RRC Bloom process for an AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention.

FIG. 8A is an illustration of exemplary ABS registry entries accordingto one embodiment of the invention.

FIG. 8B is a flow diagram of the Common Control Channel basic broadcastalert process for an Advanced Backhaul Services control link protocolprocessor according to one embodiment of the invention.

FIG. 8C is a flow diagram of the Management Entity (ME) Tier 2 channelselection and link initialization process for an Advanced BackhaulServices control link protocol processor according to one embodiment ofthe invention.

FIG. 8D is a flow diagram of the Management Entity (ME) Tier 3 channelselection and link initialization process for an Advanced BackhaulServices control link protocol processor according to one embodiment ofthe invention.

DETAILED DESCRIPTION

FIG. 4A is a table of a partial listing for the frequency availabilityfor specific radio services 47 C.F.R. § 101.101, and a proposed new bandof operation for Advanced Backhaul Services (4A-01). The new band forAdvanced Backhaul Services is not currently listed as a defined servicewithin the table for fixed microwave services. Specific embodiments ofthe disclosed invention for an Advance Backhaul service (ABS) operatewithin a band from 7125 to 8500 MHz, and include a number of tieredservices. Currently this band is not under the control of the FCC, butmay have fixed point to point services defined for government operationby the Office of Spectrum Management (OSM) within the NationalTelecommunications & Information Administration(http://www.ntia.doc.gov/office/OSM). The OSM manages the Federalgovernment's use of the radio frequency spectrum, and may be thought ofas filling a similar role for the federal government as the FCC does forthe commercial sector. Currently, most of this band is defined asgovernment exclusive operation as can be seen within the NTIA's“Redbook” defining spectrum allocations for use by the Federalgovernment(http://www.ntia.doc.gov/files/ntia/publications/redbook/2013/4b_13.pdf).The frequency band (4A-01) is provided as an example only, and otherbands of operated are contemplated for use with the embodimentsdisclosed.

FIG. 4B illustrates an exemplary deployment for occupancy of services inthe 7125 to 8500 MHZ frequency band for legacy radios and AdvancedBackhaul Services (ABS) compliant radios amongst other services. Theservices deployed within this band according to embodiments of theinvention, may be time division duplex (TDD), frequency divisionduplexed (FDD) or zero division duplexed (ZDD). FDD systems utilizeseparate frequency channels for receiving (4B-10) and transmittedsignals (4B-50) to each radio, as shown in FIG. 4B. TDD systems utilizea single frequency channel (4B-30) and alternate receiving andtransmission with the radio to which they are communicating, allowingfor the deployment of such services in the center of the operationalband, as shown in FIG. 4B. As previously discussed, ZDD systems utilizesignal processing techniques to allow the simultaneous transmitting andreceiving of signals on the same frequency channels. Generally ZDDsystems could utilize similar channels to those of the TDD operatingradios, but this is not a requirement and thus ZDD systems may be ableto use any of the FDD or TDD channels.

The spectrum in the embodiment defined in FIG. 4B is partitioned into 3Sub-Bands:

SB1=7126.5-7574.5 MHz (Channels 1 to 32) SB2=7588.5-8036.5 MHz (Channels34 to 65) SB3=8050.5-8498.5 MHz (Channels 67-98)

Additionally Channels 33 (4B-20) and 66 (4B-40) are defined as CommonControl Channels (CCC), to be used for advertising the presence of ABSdevices, intercommunication between ABS devices with respect tointerference coordination and other control and overhead functions inspecific embodiments.

Channelization

In one embodiment, a network-based registry 4C-60/4C-70 (of FIG. 4C)will provide for a maximum number of channels out of the total number ofchannels available for operation for use by a particular device (or Tieras will be explained associated with FIG. 4C), either dependent, orindependent of duplex mode of operation.

As will be discussed associated with subsequent figures, and specificembodiments, ABS services may include multiple groups of “Tiers” ofdevices, each tier having specific rules by which they must operate andresult in interference protection between and among tiers of devices(such devices being referred to as tiered service radios). Such rulesmay also provide for a fairness to access of channels to prevent somedevices from unfairly using more spectrum channels than would be fair toother devices, and preventing a reasonable number of devices within ageographic region to operate simultaneously.

For example, in one embodiment associated with FIG. 4B, the individualchannels of operation are 14 MHz in Bandwidth, as is common for fixedwireless in the United States (ranging from 3.5 MHz, 7 MHz, 14 MHz,etc). In other embodiments, such as for use is Europe, channels of 5MHz, 10 MHz, or other multiples are more common.

Any given link must use and register up to 2^(N) ^(MAX) channels of 14MHz each from amongst designated channels. FDD products typicallyregister to transmit in 2^(N) ^(MAX) ⁻¹ channels of SB1 in one directionand to transmit in 2^(N) ^(MAX) ⁻¹ channels of SB3 in the oppositedirection for a given link, however FDD products are not required to usethis SB1/SB3 duplex approach.

The selection of the number of channels for operation, as mentioned forsome embodiments, may be determined based upon the tier of service adevice belongs to, and determined according to parameters provided byaccessing a registry and may be specific to a geographic region.

In one example, for Tier 2 products, N_(MAX)=3 (e.g. 2^(N) ^(MAX) =8)resulting in 8×14 MHz, or 112 MHz would be typical in most geographicregions. In a related example, For Tier 3 products, N_(MAX)=2 (e.g.2^(N) ^(MAX) =4) resulting in 4×14 MHz, or 56 MHz would be typical inmost geographic regions. The total number of channels that can be usedby both transmitters in aggregate for any given link is M_(TOT)=2^(N)^(MAX) .

In the current embodiment, the M_(TOT) channels can be occupied byeither or both transmitters at any time for a given link, and may bedependent on the Tier of service, and geographic region. An example of ageographic region is shown in FIG. 4D by the boundary lines 4D-10,4D-15, 4D-20, and 4D-25.

Continuing with the current exemplary embodiment, M_(ACTUAL) is theactual number of channels (up to M_(TOT)), in use at any time. Once atiered service radio (or tiered device) is registered, (thus, becoming aregistered radio) to transmit M_(REG) channels in any of SB1, SB2, orSB3, such a product can transmit subject to sharing rules herein, on 1to M_(REG) channels contiguously as available. In the currentembodiment, non-contiguous Tx channels at a single transmitter are notallowed.

According to the rules of the current embodiment, all transmitters(tiered service radios for example) are fixed and registered prior tofirst usage (including Tier 3 devices). In an exemplary embodiment, nodevices are mobile.

In one embodiment, the registration may include Tx location, antennaparameters, Tx channels(s) (or channel numbers), Tx power (or max txpower), signature parameters (such as code sequences, demodulationparameters, structures, identifiable aspects of the signature radiosignals, etc.), acceptable co-channel sharing signatures (or classes ofsignatures), Tx signaling method(s), signature approach (inline versusembedded), signature power in dB relative to nominal Tx power level,and/or maximum registered Tx power. More detail and specific examples ofexemplary registry entries are discussed associated with FIG. 8A in moredetail.

FIG. 4C illustrates an exemplary embodiment of Advanced Backhaul Servicetiered service radio interconnection with an exemplary ABS deviceregistry database. In one embodiment, each tiered service radio (ortiered device) has specific rules and procedures, which are required tobe followed, except for a legacy device. The tiered service radiosprovide for interference protection for legacy devices, or from otherdevices at the same or lower tier. Membership to a tier varies basedupon the specific tier. For example in the embodiment of FIGS. 4A and4B, utilizing spectrum with fixed point to point devices operating underexisting rules, such devices as currently in use for Federal point topoint wireless communications would be deemed to be Tier 1 devices4C-10. Such currently deployed devices would be deemed “legacy” Tier 14C-10, where new devices which also belong to existing government users,would be deemed “incumbent” Tier 1 devices 4C-20, and may have specificrequirements for the deployed equipment differing from the currentlydeployed legacy Tier 1 devices. In one embodiment Tier 1 devices 4C-10,4C-20 would be protected from interference by requiring lower tierdevices (4C-30, 4C-40) to perform a registry look up for a specificgeographic region. Specific criteria, in some embodiments, is passed tothe registry so as to retrieve information related to the registeredradios on interest. In this embodiment, it would be a requirement of thedevices, of lower tiers of service performing the registry look up,utilizing specific criteria, to be able to determine, or to be provided,their current geographic coordinates. In other embodiments, the specificcriteria may be a subset or inquiry criteria and be within the tieredservice radio and used to filter the information returned from theregistry. In further embodiments, specific criteria such as geographiclocation, tier of the inquiring device, etc., may be passed to theregistry as inquiry criteria and the filtering and/or selection ofinformation performed within the registry completely. In yet furtherembodiments, the selection of information from the registry based uponthe specific criteria may be performed on one or both of either theinquiring tiered service radio or the registry apart (or incombination).

Returning to the current description, the only protection a legacy Tier1 device 4C-10 would have is the registry 4C-70 with a pre-definedexclusion zone associated with a geographic location. Such an exclusionzone within may be defined by one or more center points, and a radiusfrom each center point, or another definable geographic shape such as arectangle, or an ellipse, or the like. An example of such an exclusionzone is provided in FIG. 4D, associated with exclusion zone 4D-35.Exclusion zone 4D-35 provides for an ellipse as defined within theserver 4C-60 and registry database 4C-70. Lower tier devices, such asTier 2 Devices 4C-30 and Tier 3 Devices 4C-40, connect to server 4C-60and registry database 4C-70 via network connections 4C-35, 4C-45, and4C-65, and over an interim network 4C-50 in some embodiments. Such anetwork 4C-50 may be a private network, or the public Internet, or both.Additionally, Incumbent Tier 1 devices may include a network connection4C-25 in some embodiments. Incumbent Tier 1 Devices 4C-20 mayadditionally become a registered radio with the registry database 4C-70in some embodiments, or may transmit an alert message advertising theIncumbent Tier 1 Device's presence, or perform both registration as wellas advertisement. Such an advertisement may be performed in a number ofways including on the so-called common control channels (4B-20, 4B-40)and associated with FIG. 4B. In other embodiments, alerts may betransmitted inband so as to allow for an accurate assessment of thereceived signal from the Tier 1 device, and to determine an acceptabletransmission power so as to ensure no detrimental interference to theTier 1 Device. An example of Incumbent Tier 1 devices operatingutilizing in-band alert transmission is provided associated with FIG.4D. Incumbent T1 Device (T1-I) 4D-40-A is in communication with T1-I4D-40-B, both transmitting an alert signal, including informationidentifying the device and either including the transmitted power withinthe alert, or retrievable from the registry database. Additionalinformation may be included with the transmission or within the registryas well such as locations of the devices, and frequencies or operation,and mode (TDD/FDD/ZDD) of the device, and the like. More detail relatedto embodiments of the registry entries are provided associated with FIG.8A. For example, such information can be used to determine thepropagation path loss to the transmitter or to estimate path loss topotential receivers associated with the stations. Tier 2 devices4D-60-A, 4D-60-B may utilize transmission limits as determined from suchparameters so as to operate in closer proximity to the T1-I devices4D-40-A and B, rather than simply utilizing an exclusion zone.

Referring back to FIG. 4C, Tier 2 Devices are registered users (orregistered radios) and are provided with a license, which offersinterference protection relative to other Tier 2 devices, and Tier 3devices. Tier 2 devices (T2), in some embodiments, have no interferenceprotection from Tier 1 devices (Legacy or Incumbent). To receive alicense, operators of T2 devices may pay a fee that may be determined byin a number of ways, in various embodiments. Such a fee may be basedupon:

-   -   i. number of channels up to a maximum for initial registration,        and annual usage per link for a specific geographic region,        and/or    -   ii. by Auction, and/or    -   iii. by Status (such as, for example only, providing a service        deemed a public good)

Exemplary rules that may be required for Tier 2 devices include:

-   -   Tier 2 users must not use, or must vacate upon detection,        channels occupied by Tier 1 users.    -   Tier 2 users must occasionally re-check the registry database        (based upon time, duration, or the like).    -   Tier 2 devices must advertise their presence by transmitting an        Alert signal including a T2 Alert Signature, and registering        within the registry data base 4C-70 (or becoming a registered        radio), including the start time of their active operation and        other details, such as for example, described associated with        FIG. 8A.

An example of a T2 device being prevented from operating, as accordingto the foregoing rules, is provided associated with FIG. 4D, and T2device 4D-45. The T2 device 4D-45 is geographically too close to T1-Idevice 4D-40-A, and upon performing a scan of the radio environmentdetects alerts from the T1 device (for example a signature radio signalin one embodiment), and thus T2 device 4D-45 is prevented from operatingon the same channel(s) on which T1-I device 4D-40-A operates. If otherunoccupied channels are available, the T2 device 4D-45 would be not beprevented from attempting operation on those alternative channels,unless those channels were otherwise not allowed due to yet anotherdevice's exclusion zones, or alert signature transmissions that could bedetected.

An example of rules for an embodiment for T2 devices to achieveinterference protection from other T2 users is:

-   -   Tier 2 users must not use channels already occupied by other        Tier 2 users as either:        -   i. Detectable at a threshold with a valid Tier 2 signature,            or        -   ii. Registered (as a registered radio) in a look up for a            geographic location within a Tier 2's exclusion zone, unless        -   iii. Existing channel occupant Tier 2 user with “precedence”            agrees to accept the presence of the new channel occupant            tier 2 user. For these purposes precedence is defined as the            device having initiated continuous operation on a            channel (s) earlier in time, as entered within the registry.

Just as Tier 1 devices, in the current embodiment, have priority and areprotected from interference from Tier 2 devices, Tier 2 devices havepriority and are protected from interference from Tier 3 devices 4C-40,of FIG. 4C. In this embodiment, priority indicates that a device may beplaced in the presence and cause interference to another device of lowerpriority, thus causing the lower priority device (or lower Tier device)to modify operating parameters (or adjustable network parameters) suchas channel of operation, transmission power, antenna selection, transmitor receive antenna beam patterns, polarization, or the like. Furtherupon alert detection, registry entry read, or direct notification to thelower Tier device by a higher Tier device, that a tiered service radiois present, the lower tier device as a lower priority tiered serviceradio must cease operating (in one embodiment) and re-initializeoperating according the rules associated with that Tier's operation. Inspecific embodiments, Tier 2 devices, being licensed and registered (asregistered radios), have priority over Tier 3 devices (T3), and receiveinterference protection from the Tier 3 devices. According to oneembodiment, Tier 3 devices must be certified to obey operating rules oftheir Tier, but would not be licensed to a channel or geographic regionand may not be required to pay any type of a fee associated with alicense. Example rules for operating Tier 3 devices are as follows,according to one embodiment:

Tier 3—Unlicensed Users

-   -   Allowed to use up to “unlicensed max” number of channels for a        specific geographic region as determined by registry look up,        and    -   Wherein Tier 3 users must not use, or must vacate upon detection        of any Tier 1 or Tier 2 user at any time    -   Wherein Tier 3 users must certify:        -   i. Detection capability for Tier 1 and Tier 2 signatures,            and        -   ii. The ability to access the registry prior to transmitting            on the ABS channels

The various tiers of devices have interference priorities and obeysharing rules. However, specific embodiments may provide for certainchannels to be reserved for specific tiers of operation to ensure fairaccess to the spectrum resources. For example, in one embodimentassociated with FIG. 4B, Channels 1, 2, 34, 65, 97, 98 plus otherchannels as designated for any given geographic zone within the registryare Tier 2 Exclusion Channels. Tier 2 products can use such channels butreceive no protection from Tier 3 transmitters. This ensures that Tier 3devices can never be completely precluded from all operation in anygiven geographic region by a high density of Tier 2 devices.

As described above, in embodiments of ABS services, T1-Incumbent, T2,and T3 devices are required to transmit an alert having a signaturesequence. In other embodiments, only T3 devices, or both T3 and T2devices are required to transmit an alert signature. The alert signaturemay vary in different embodiments of the invention, and may betransmitted on the common control channels in some cases, or within theband of operation (in-band) in other embodiments. Further, when thealerts are transmitted in-band they may be “in-line” or “embedded”. Oneexample of an embedded signature sequence was disclosed associated withco-pending application U.S. Ser. No. 13/763,530, the entirety of whichis incorporated herein by reference. The structure of the alert signalsand the signatures within them are described in further detail withrespect to FIG. 5D, FIG. 5E, FIG. 5F, and FIG. 5G.

In one embodiment, all transmitters required to transmit an alert musttransmit signatures having at least 0.01% (or −40 dBc) of the nominaltransmit energy in every 1 s period (P_(NOM)×1 s) based upon relativetransmit time and relative transmit power.

In one exemplary embodiment, a signature of duration 100 μs can betransmitted either in-band/in-line, in-band/embedded, or on the commoncontrol channel. Further embodiments may include transmitting an alertsignature from a receiver antenna, so as to enhance the potential fordetermining interference potential and accuracy or to aid the estimationof the interference potential from other ABS devices. Such an approachmay be applicable for ZDD and/or TDD based devices, or FDD devices anyof which may utilize interference cancelation approaches at the receiverto remove the transmitted alert. Alternatively such an approach mayutilize in-line bursts of the alert signal in designated non-receptiontime periods at the receive antenna.

In one example of inline signaling for an in-band/inline alert, a burstsignature at P_NOM transmission power level for 100 μs is utilized, oneevery second. In another example, an alert signature may be transmittedmultiple times per second, but at a power level of

$\frac{P_{NOM}}{\frac{T_{SIG}}{100\mspace{14mu} {us}}}$

so as to result in the same integrated power over the 1-second period.As a result, a receiving device can be sure of the integrated receivepower per unit time, relative to the nominal transmission power of thesignal carrying information. Such a process of interference estimationfurther enhances the ability of the detecting device to assess thepotential for interfering with the detected device upon beginningtransmissions from the detecting device.

In another embodiment where the alert is transmitted on the CommonControl Channel (4B-20 and/or 4B-40) one alert will be transmitted at arandom time within every 1 ms time period, including a 100 μs burstsignature at P_(NOM), again allowing for the estimation of the powerlevel of the detected alert relative to the information signal from thattransmitting device.

The common control channel is further available for non-protectionsignaling broadcasts instead of inline signatures. For example, thecommon control channel may be utilized for intercommunication betweentiered service radios, in contrast to simply advertising the presence ofthe device so as to make tiered service radios of a relative lower tierrefrain from interfering with the instant tiered service radio (e.g.protection signaling).

One embodiment of the common control channel is available for limitedframe exchanges for any Tier 2 or 3 transmitters without currentregistration subject to such exemplary restrictions as:

-   -   P_(LIMIT)=P_(NOM), and modulation is only within channel    -   Max 100 us frame duration that is randomly chosen    -   Max 1 frame per TX Period of 1 ms    -   Max 100 frames per TX per second    -   At least one signature frame per Tx per second

One embodiment of a signature and associated payload will now bediscussed, which includes a unique 32 bit address assigned as a 16 bitmanufacturer code and a 16 bit random address. The alert may alsoinclude the transmission or reception channels, and may be modulatedutilizing non-coherent DQPSK or DBPSK using a code sequence. In variousembodiments, the code sequence is a direct sequence spreading code, andutilize one or more of a Barker, P N, maximal length code, CAZAC, Gold,Zadoff-Chu, and the like.

In one example having 1 signature of length 100 us in a 14 MHz channelresults in ≈12.39 Msym/s or 1238+ symbols/100 us when using a rootraised cosign filter of 1.13. The information bits may further utilize a½ rate Reed Muller or Reed Solomon Code (for Parity Check), and bemodulated according to DQPSK. One embodiment would then result in atleast 37 spreading “chips” per bit, with 32 bits of information.

Alternative embodiments of the structure and processing of alerts andtheir transmission and associated layered protocols will be providedassociated with subsequent figures.

Transmission Power of ABS Signals

Associated with the example embodiment of FIG. 4B, and having 14 MHzchannels, the power limit for a given device may be given by:

$P_{LIMIT} = {P_{NOM} + {10*{\log \left\lbrack \frac{{Aggregate}\mspace{14mu} {Information}\mspace{14mu} {Rate}}{28*M_{ACTUAL}} \right\rbrack}}}$

Where P_(NOM) is the nominal power level determined from the registryfor the given tier of service, and the geographic operating region.

Further the maximum equivalent (or effective) isotropically radiatedpower for a given tiered service radio is determined by

Max EIRP=P _(LIMIT) *G _(TxMAX)

where G_(TxMAX) is max Tx antenna gain limit for a given geographiczone.

Each ABS device must further demonstrate and be certified to performtransmit power control over P_(NOM)−10 dB to P_(MAX) (whereP_(MAX)<P_(LIMIT)).

As previously described, the alerts may be utilized so as to determinethe potential for interfering with other devices within the area suchthat antenna and transmission parameters (as adjustable networkparameters) may be adjusted so as to reduce the potential forinterfering with higher tier devices, or devices of the same tier butwith a earlier occupancy of the channel (precedence). As will bediscussed further, upon the detection of an alert from a device of thesame or lower tier, but with lower precedence if from the same tier,procedures are disclosed by which the two devices may cooperativelyreduce the interference levels to acceptable levels, or by which thelower tier or lower precedent device may be forced to discontinuetransmission all together. Such cooperative interference mitigationapproach will be discussed associated with subsequent figures, inparticular FIG. 8C and FIG. 8D.

Turning now to FIG. 4E, an exemplary embodiment of a deployment ofintelligent backhaul radios (IBRs) is deployed for cellular base stationbackhaul with obstructed LOS in the presence of Tier 1 radios accordingto an embodiment of ABS services.

FIG. 4E illustrates a deployment scenario according to one embodiment ofthe invention. In this example, Incumbent Tier 1 device (T1-I) 132 autilizes an unobstructed line of sight wireless link 136 to T1-I 132 b.The T1-Is have a relatively narrow beam (e.g., 3 dB width of 2 Degreesin both azimuth and elevation). A tall building 312 is located betweenT1-I 132 a and T1-I 132 b. The building 312 is short enough that it doesnot adversely impact link 136 because each T1-I has a relatively narrowbeam.

FIG. 4H illustrates a T1-I antenna pattern having a similar main antennabeam width and other antenna pattern attributes as the T1-Is 132 a, 132b of FIG. 4E. It is relevant to note that while the T1-I antenna patterndepicted in FIG. 4H possesses a narrow 3 dB main beam width 4H-40relative to the peak gain 4H-10 in the antenna bore sight direction,there remains the possibility for signal reception from angles beyondthe 3 dB beam width points, but with lesser relative antenna gainlevels. For example, the gain level at twice the 3 dB beam width may beas significant as −10 dB or −15 dB relative to the main bore sight gain4H-10. Furthermore, the gain at side lobe 4H-20 remains within −20 dB,in this example, relative to the peak bore sight gain 4H-10, and islocated at roughly 3 times the angular separation from the bore sightdirection as the 3 dB main beam radius. In contrast, antenna nulls,including nulls 4H-30, are points where the residual gain from the T1-Iantenna is at a significant minimum level and are generally interspersedbetween side lobes or other higher gain portions of the antenna pattern.The antenna pattern depicted in FIG. 4H represents a typical T1-Iantenna pattern, such as one produced by so called parabolic dishesincluding, generally, a circularly symmetric antenna gain pattern aboutthe bore sight.

As discussed in additional detail in this disclosure and the co-pendingapplications previously incorporated by reference, the use ofmulti-element antenna systems, in some configurations, allows an antennaarray's beams, side lobes, and nulls to be advantageously directed. Bythe advantageous angular placement of an antenna array's main gain lobe,and the placement of lower gain portions of the antenna array's gainpattern in specific other directions, a desired link may be maintainedwhile managing the level of undesired signal transmitted to or receivedfrom other transceiving radios (including T1-Is) in the area. Theantenna arrays may utilize adaptive techniques incorporatingtransmission null steering or reception null steering approaches. In oneembodiment, adaptive antenna array processing, including null steeringalgorithms, are utilized to allow for the deployment of RE-IBR 4E-20 andAE-IBR 4E-10 of FIG. 4E (as either T2 or T3 devices) in the presence ofT1-Is 132 a and 132 b so as to not impact the T1-Is 132 a,b receiverperformance by reducing interfering signal levels from each IBRimpinging upon the T1-I antenna gain patterns. As estimate of therelative interference from the T2 or T3 devices to the T1-I devices maybe determined utilizing the detection of the alert signature transmittedfrom the T1-I devices.

In one embodiment, the antenna elements 352A of FIGS. 3A to 3H (e.g.,utilized by IBR 4E-10 and 4E-20) have a 3 dB antenna beam width inelevation of 15 degrees and a 3 dB antenna beam width of 30 degrees inazimuth. Such individual antenna pattern radiation patterns may causeinterference to deployed T1-Is in the geographic area. In one example,the signal transmissions from RE-IBR 4E-20 to T1-I 132 a via propagationpath 4E-60 are received at a sufficient level so as to cause adegradation of the T1-I link 136 performance. In another example, asignal transmitted from AE-IBR 4E-10 along a signal propagation path4E-70 is scattered from building 312 and received in a side lobe of theantenna pattern of T1-I 132 b at a sufficient level to also impact theT1-I to T1-I link performance.

In one embodiment, the RE-IBR 4E-20 and AE-IBR 4E-10 utilize amulti-element antenna array such as depicted in FIG. 3I. Such an antennaarray configuration allow for spatial array processing. Such spatialarray processing may include phased array processing, digital beamforming, transmission null steering, elevation and azimuth beamsteering, antenna selection, beam selection, polarization adjustments,MIMO processing techniques, and other antenna pattern modification andspatial processing approaches for both the transmission and reception ofsignals. It will be appreciated that other antenna array configurationsmay be used, which have more or fewer antenna elements than theexemplary IBR antenna arrays depicted in FIGS. 3I and 3J, and which havedifferent geometrical arrangements, polarizations, directionalalignments and the like.

Embodiments of the invention are advantageous because the impact to theT1-I link performance can be reduced or eliminated completely whileallowing for the deployment of the IBR 4E-10 and IBR 4E-20 in the samegeographical region as the T1-I devices 132 a and 132 b with sufficientinter-IBR link 4E-50 performance. In some embodiments, IBR deploymentsmay be enabled in the same geographical areas and within the samefrequency bands, and in further embodiments such deployments may be in aco-channel configuration amongst a T1-I link and an IBR link, whileallowing for sufficient performance between IBR 4E-10 and IBR 4E-20.

With reference to FIGS. 4F and 4G, specific embodiments of Tier 2 orTier 3 devices are described with respect to reducing interference toco-channel Tier 1 devices according to an embodiment of the ABSservices.

FIGS. 4F and 4G illustrate additional exemplary deployments of IBRs inthe presence of T1-Is. FIG. 4F is a side perspective view of elements ofa deployment embodiment example, and FIG. 4G is a top perspective viewof the deployment embodiment. It should also be noted that somegeometrical differences exist between FIG. 4F and FIG. 4G to provideillustrative descriptions. Where FIG. 4F and FIG. 4G are in conflict orotherwise are inconsistent, the differences should be consideredalternative embodiments.

Intelligent backhaul radios RE-IBR 4F-20 and AE-IBR 4F-25 are deployedwith configurations as previously discussed in the related embodimentsof IBRs 4E-10 and 4E-20. The IBRs 4F-20 and 4F-25 are deployed forcellular base station backhaul with obstructed LOS propagation link4F-60 according to one embodiment of the invention.

In FIGS. 4F and 4G, T1-I A 4F-05 and T1-I B 4F-10 are deployed forcellular base station backhaul with unobstructed line of sight (LOS)propagation link 4F-15. T1-Is 4F-05 and 4F-10 are deployed within thesame geographical region of the IBRs 4F-20 and 4F-25. Each of T1-I 4F-05and 4F-10 uses an antenna pattern, with 3 dB main beam width. Additionalproperties of T1-Is 4F-05 and 4F-10 are, in one embodiment, the same asthose described with respect to T1-Is 4G-05 and 4G-10 of FIG. 4G.

In the embodiment shown in FIG. 4F, antenna elements 352A (see, forexample, FIGS. 3A-H) are utilized by IBR 4F-20 and 4F-25 and have a 3 dBantenna beam width in elevation of 15 degrees and a 3 dB antenna beamwidth of 30 degrees in azimuth. Such individual antenna patternradiation patterns may cause interference to deployed T1-Is in thegeographic area. In one example, the signal transmissions from RE-IBR4F-20 to T1-I 4F-05 via propagation path 4F-30 are received at asufficient level to cause a degradation of performance of the T1-I link4F-15. In another example, a signal transmitted from AE-IBR 4E-25 alongsignal propagation path 4F-40 and 4F-45 is scattered and attenuated frombuilding 4F-50 but has a sufficiently low level so as to not causeperformance degradation to intended signal reception at either of T1-I4F-10 or IBR 4F-25.

As explained above, in FIG. 4F, RE-IBR 4F-20 and AE-IBR 4F-25 aredeployed for cellular base station backhaul with obstructed LOSpropagation link 4F-60. Additionally, with respect to the presentembodiments of FIGS. 4F and 4G, RE-IBR 4F-20 and AE-IBR 4F-25 utilize amulti-element antenna array, such as antenna array 348A of FIG. 3A or3B. The antenna array 348A allows for various spatial array processing.As described above, such spatial array processing may include phasedarray processing, digital beam forming, transmission null steering,elevation and azimuth beam steering, antenna selection, beam selection,polarization adjustments, MIMO processing techniques, and other antennapattern modification and spatial processing approaches for both thetransmission and reception of signals. It should be noted the currentembodiment is only one configuration, and that other embodiments mayutilize more or fewer antenna elements and with varying geometricalarrangements, polarizations, directional alignments and the like.

Embodiments of the invention relate to determination of IBR networkparameters (including adjustable network parameters) and theinstallation and commissioning process of remote end IBRs (RE-IBRs) andAggregation End IBRs (AE-IBRs). A detailed process for installing andcommissioning the IBRs (or tiered service radios in general) isdescribed in further detail below. These processes and/or some of theprocess steps may be may be performed using one more of IBRs and IBCs(or Intelligent Backhaul Controller) of FIG. 4G, or elements of anIntelligent Backhaul Management System (or IBMS 420 in FIG. 4G)including IBMS Private Server 424, IBMS Private Database 432, IBMSGlobal Server 428, IBMS Global Database 436, the Private Database 440,and the processing and storage elements accessible utilizing the publicinternet such as the Cloud computing resource 456, Public Database 452,and Proprietary Database. Additional details describing the IBC and IBMSand exemplary relationships to IBRs are found in co-pending applicationU.S. Ser. No. 13/271,051 for the Intelligent Backhaul System (or IBS),the entirety of which is incorporated by reference herein.

During installation or during deployment and operation of the IBRs4F-20, 4F-25, the IBS, IBMS and other public and private networkelements such as the registry server 4C-60 and database 4C-70 (which maycollectively include a registry in some embodiments) may use informationstored with one or more network elements to determine or aid in thedetermination of IBR operational parameters (adjustable networkparameters for example) for allowing co-band or co-channel operationwith manageable interference impact to and from T1-Is 4F-05 and 4F-10 orother aforementioned services within a geographic zone, or within aknown radio frequency propagation distance.

Exemplary IBR operational parameters (adjustable network parameters)include but are not limited to: the selection operational frequencies;the modification of transmitter antenna patterns; the modifying orselection of antenna polarization or spatial patterns; the selection ofspecific antennas from a set of available antennas; the selection oftransmission nulls, reducing the interference impinging upon othersystems; the selection of receiving or transmission digital beam formingweights, or algorithmic beam forming constraints; the physical movement,placement, alignment, or augmentation of one or more antenna elements orantenna arrays by electrical, or electromechanical control or by arequest for manual adjustment or augmentation during or afterinstallation; the modification of transmission power; and the selectionof interference margin values for the reduction of the risk ininterfering existing systems.

In one embodiment, the determination of the IBR operational parameters(adjustable network parameters) is performed utilizing an algorithmbased at least in part on the location of the T1-Is 4F-05 and 4F-10 andtheir radiation parameters. This information may be stored in theUniversal Licensing System (ULS) operated by the Federal CommunicationsCommission (FCC), or on other public or private databases or theregistry server as shown in FIG. 4C (4C-60/4C-70). In one embodiment,ULS information and associated radiation parameters in combination withradio frequency propagation models are utilized to determine the levelto which operation of an IBR, under various IBR operational parameterswould interfere with one or more Tier 1 Incumbent or Legacy services. Inanother embodiment, reports of received signal are provided by IBRs,possibly in combination with existing IBR operational parameters, to theIBMS for use in IBR operational parameter determination. Such reportsmay be stored by the IBMS and used alone or in combination with T1-I orT1-L radiation parameter information from public or private databases toperform IBR operational parameter selection.

Further embodiments may include an iterative method. For example, theIBRs may report received spectral measurements and configurationparameters to the IBMS, which performs selection of some or all for theoperation parameters, and passing the parameters to respective IBRs. TheIBRs may then perform additional or refined scanning upon initialoperation prior to the determination of subsequent IBR operationalparameters.

Upon initiating the configuration process in this embodiment, therespective IBRs perform a scan of receive channels to detect existingT1-Is. The scan process, in some embodiments, produces scan data. TheIBRs then report their respective antenna configurations and scanresults (scan data) to the IBMS. Note that in other embodiments, acentralized server may not be used at all, allowing for a distributeddecision process based upon rules. Returning to the current embodiment,the IBMS, will determine, assuming another channel may not be used, thelevel of interference the T1-I will receive. In some embodiments, thisdetermination is based also upon received signatures levels (signatureradio signal levels for example) or alert level per the disclosedinvention. The interference may be determined utilizing IBR effectiveantenna pattern adjustments and, optionally, associated informationretrieved from a database of T1-I parameters. In some embodiments, theeffective antenna pattern adjustments may include the use oftransmission beam nulling from the required one or more IBRs to furtherreduce the interference levels which may be received at the T1-I, whilemaintaining a minimum required performance between the respective IBRs.In one embodiment, an interference margin is also calculated. Theinterference margin is used as an additional reduction of the requiredinterference to the target T1-I. The interference margin may be based ona fixed amount; a level of uncertainty of the predicted interference, anamount based upon the reliability or predicted accuracy of interferencecalculations, or based upon using or the availability of, the specificvalues of T1-I antenna and operating transmission parameters retrievedfrom a database.

In some embodiments, the RE-IBRs and AE-IBRs may operate on channels forwhich no interference is detected, but are within a predetermineddistance of T1-Is. The distance is determined based on the geographiclocation of the IBRs and the T1-Is. The location of the T1-Is may bedetermined by accessing, for example, the FCC (ULS) database. In suchsituations, the IBMS may utilize an interference margin value or otheroperational constraint value based upon propagation models to furtherreduce the likelihood of interfering with the T1-I.

In some embodiments, co-existence of the IBRs with FDD T1-Is may berequired. In these embodiments, interference margins or operationaltransmission constraints, including transmission beam nulling, may needto be calculated. For example, in one embodiment, the selection of thetransmission antennas to utilize for receive during a scan procedureduring configuration may allow for enhancement of transmit beam formingand transmit nulling operations and may further aid in the determinationof values related to transmission beam nulling.

In some embodiments, received signals transmitted from a T1-I 4F-05operating in FDD are detected during a scan procedure at an IBR 4F-20.However, the IBR to IBR link, in one deployment, is configured tooperate on the specific FDD paired frequency co-channel used forreceiving by the FDD T1-I 4F-05 as determined, for example, by the IBMS420 in FIG. 4G and FCC data base records in a public data base 452, orthe registry server 4C-60 and database 4C-70. In this embodiment,transmission beam nulling weighs for the T1-I 4F-05 receiving channel(uplink paired channel used by T1-I 4F-05 for receiving from T1-I 4F-10)or other transmission constraints may be determined based upon thereceived signals at the IBR 4F-20 in the paired (downlink paired channelas used by T1-I 4F-05 to transmit to T1-I 4F-10) channel, despite thefrequency difference for the transmission channel. Such calculations mayutilize propagation modeling to determine interference levels, reportedmeasurements by the IBR to determine the level of frequency flat orfrequency selective fading, and data base values related to T1-Iparameters. In this embodiment, these calculations involve a constrainedtransmission beam forming calculation for example, including aninterference margin based at least in part upon the determined level offlat or selective fading of the scanned signal on the paired band.

Embodiments of the invention allow for IBR adjustable network parametersto be selected to avoid co-channel operation with T1-Is. In deploymentswhere co-channel operation between the IBRs and T1-Is is not avoidable,the impact on link performance to the T1-I 4F-10 and from T1-I 4F-05 canbe reduced or eliminated completely while allowing for the deployment ofthe IBR 4F-20 and IBR 4F-25 in the same geographical region withsufficient inter-IBR link 4F-60 performance. In some embodiments, theIBRs may be deployed in the same geographical areas and within the samefrequency bands as T1-Is. In some embodiments, the IBRs and T1-Is may bedeployed in a co-channel configuration, while still allowing forsufficient performance between IBR 4F-20 and IBR 4F-25.

Referring now to FIG. 5A, an embodiment of an IBR including a SignatureLink Processor (SLP) is depicted. A number of the blocks common withFIGS. 3A and 3B are shown, whose functioning is generally describedassociated with the foregoing description. Relative to FIG. 3B, FIG. 5Aprovides for a modified IBR MAC 512A, and an additional block referredto as a Signature Link Processor (SLP) 500.

Embodiments of IBR MAC 512A generally incorporate the functionality ofthe various embodiments of IBR MAC 312A. Some Embodiments of IBR MAC512A may additionally include MAC processing supporting the optimizationof the wireless links utilizing ECHO devices as described more fully inco-pending application U.S. Ser. No. 13/763,530, the entirety of whichis incorporated herein by reference. Additionally some embodiments ofIBR MAC 512A will support peer to peer and communications with otherdevices (e.g. ECHO devices) utilizing a Signature control channel forthe transfer of control information.

Embodiments of the Signature Link Processor (SLP) 500 provide for thereception and insertion of an additional wireless communications channelreferred to as a Signature control channel in specific embodiments.Associated with IBR transmission, the Signature Link Processor receivestransmit symbol streams (1 . . . K) from IBR Modem 324A and provides thesame transmit symbol streams (1 . . . K) to the IBR Channel MUX 328Awith additional Signature control channels added to the individualstreams, if such processing is enabled. In some embodiments whereSignature control channels are not actively associated with any specifictransmit symbol stream, the transmit symbol streams are passed to theirrespective with no addition of Signature control channel signal.Embodiments of the SLP may provide for a unique Signature controlchannel to be added to each of the respective transmit symbol streams.In other embodiments the SLP may provide for the components of thecontrol channel or the control channel in entirety to be added commonlyto all transmit symbol stream in a related fashion.

In one exemplary embodiment utilizing a common control channelstructure, a direct sequence spread spectrum (DSSS) pilot signalutilizing a first orthogonal code will be added commonly to all streamsprocessed for transmission by the SLP. Additionally, in the instantembodiment, each individual stream will receive a respective second copyof the DSSS pilot signal, but modulated with a differing orthogonal coderespectively associated with the individual transmit symbol streams.Such modulation may be accomplished using modulo 2 additions,multipliers, or bi-phase modulators as known in the art. The individualorthogonal codes may additionally be modulated by information bits inthe form of the IBR_SLP_Data transmit data interface stream, resultingin a Signature control sub-channel symbol stream. One such referenceteaching DSSS and CDMA modulation and demodulation techniques is CDMA:Principles of Spread Spectrum Communications, by Andrew J. Viterbi(Addison Wesley Longman, Inc., ISBN: 0-201-63374-1). Some embodiments ofthe Signature control channel having a specific structure utilizingmultiple sub-channels are referred to as a common control channel. Theuse of either term in specific instances should not be consideredlimiting, and in some cases is utilized interchangeably.

Embodiments of the Signature Link Processor (SLP) 500 further providefor the reception and demodulation of Signature control channelsinserted into one or more transmitted symbol streams by other devices,such as an ECHO device. Associated with IBR reception, the SignatureLink Processor 500 receives receive symbol streams (1 . . . L) from IBRChannel MUX 328A and provides the same transmit symbol streams (1 . . .L) to the IBR Modem 324A, with the detection and or demodulation of anyassociated Signature control channels within the individual streams, ifsuch processing is enabled. The resulting demodulated data from theSignature control channels is provided to the IBR MAC 512A by the SLP500 as IBR_SLP_Data. Embodiments of the SLP may provide for a uniqueSignature control channel to be received and demodulated associated witheach of the respective receive symbol streams. In other embodiments theSLP may provide for the components of the control channel or the controlchannel in entirety be detected and demodulated commonly from allreceive symbol streams.

In alternative embodiments, with appropriate interfaces, the SLP may beplaced between the IBR Channel Mux 328A and the IBR RF 332A so as toallow for a single Signature control channel on a per transmit orreceive chain basis rather than on per symbol stream basis.

In yet further alternative embodiments, a similar per chain Signaturecontrol channel result may be obtained utilizing the SLP placement asshown in FIG. 5A but with amplitude and phase weightings so as to causethe IBR Channel MUX to achieve the intended result. Such combinations ofIBR Channel MUX processing with coordinated SLP processing furtherallows for additional control of capabilities of mapping specificSignature control streams with specific transmit or receive chainsassociated with the IBR RF 332A.

FIG. 5B is an exemplary block diagram of an embodiment of the SignatureLink Processor (SLP) 500. The SLP controller provides for interfacingthe SLP_Data, RRC and/or RLC with the Signature Control Channel Modem(or SCCM) data and control information denoted as SCCM_Data-(1 . . . KL)and SCCM_Ctrl-(1 . . . KL) via communication with the individualSignature Control Channel Modems (510B-1 . . . 510B-KL). Such interfacesallow for the interchange of data, including and control informationwith the individual modems. For example the relative signal level andtiming of the individual per stream Signature control channels andsub-channels within transmit symbol streams may be set utilizing thecontrol information contained within the SCCM_Ctrl-kl signals (where klvaries linearly from 1 to KL). Additionally the correlated signal levelof a Signature control channel or sub-channel, the received signal levelindication of all the signals, and the timing information of thereceived signals may be additionally communicated from the individualSCCM Modems to the SLP Controller 520B, and to the RLC, SLP_Data, andRRC subsequently. It should be understood that the SLP_Data signal ofFIG. 5B corresponds to the IBR_SLP_Data signal of FIG. 5A. However, asthe SLP will be disclosed as being utilized in subsequent embodimentsassociated with ECHO devices, the naming within FIG. 5B is more generic.

Additionally, the DRx-kl signals (where kl varies from 1 to KL) providefor digitally sampled signals associated with the 1 to L receive symbolstreams, in some embodiments. The DRx_Out-kl signals (where kl variesfrom 1 to KL) are respectively coupled to DRx-kl, to provide for a passthrough operation of the respective DRx-kl signals, for example when anSLP is utilized within an IBR. Such a pass through coupling, in someembodiments, allows for the coupling of the receive symbol streams fromthe IBR Channel MUX 238A to the IBR Modem 324A. In some alternativeembodiments where the SLP is utilized within a repeater device, such DRxOut-kl signals may not be utilized by the repeater device and may not bedepicted as external ports to the SLP in such embodiments.

The DTx_In-kl and DTx_Out-kl signals (where kl varies from 1 to KL)provide for a digitally sampled signals associated with the 1 to Ktransmit symbol streams respectively input and output from SLP 500, insome embodiments. An individual Signature Control Channel Modem 510B-kl,provides a modulated control channel (MTx-kl) to a respective exemplaryAdder 514B-kl, which combines MTx-kl with the input transmit symbolstream DTx_In-kl. Adder 514B-kl in turn provides the Signature ControlChannel Signal DTx_Out-kl. In embodiments where no input to a particularDTx_In-kl is provided, the MTx-kl signal is provided directly asDTx_Out-kl.

Note that KL need not be equal to either K or L. In some embodimentswhere there is a one to one correspondence between transmit symbolstreams and Signature control channels (or sub-channels in a commoncontrol channel structure), KL must be equal to or greater than K. Incases where KL (the number of SCCMs) exceeds K (the number of transmitsymbol streams) the excess SCCMs may not be utilized for transmission,or may be used for other purposes. One such purpose would be for usededicated to a transmit chain, such as might be used with a single highgain antenna panel for example.

Further, when there is a one to one correspondence between the number ofreceive symbol streams and the number of Signature control channelsassociated with these streams, KL (number of SCCMs) must be equal to orexceed L (number of receive symbol streams). In the case where KLexceeds L, a number of the SCCMs may remain unused for reception ofSignature control channels, or may be utilized for other purposes suchas receiving Signature control channels from individual receive chains.

FIG. 5C is an exemplary block diagram of an embodiment of a Signaturecontrol channel modem 510B-kl. Digitally sampled receive symbol streamDRx-kl is coupled to Signature Control Channel Detector/Synchronizerblock 570C, which preforms timing synchronization with the DSSS signalswithin the input signal, and detects the presence and associated signallevels (in uncorrelated and correlated levels for example, Io, Ec, Es,Ec/Io and/or, Es/Io), and associated timing information and provides oneor more of the determined values to the Modem Timing Controller 550C.The Modem Timing Controller 550C, in one embodiment, utilizes the timingand received Ec/Io information to trigger the demodulation and ortransmission of Signature control signals respectively associated withthe Digital Demodulator 560C and the Digital Modulator 580C. Thedigitally sampled receive symbol stream DRx-kl is additionally coupledto the Digital Demodulator 560C, which upon receiving SCCM_Ctrlconfiguration information, and timing information from the Modem TimingController dispreads and demodulates the DSSS signals associated withthe Signature Control Channel and any associated pilot, and any datasub-channels for SCCM Data. The SCCM_Ctrl configuration information, inspecific embodiments, may contain a specific PN code, Gold code, orother code to be utilized for spreading and dispreading in the SCCM 510Bfor use in Digital Demodulator 560C and Digital Modulator 580C.Additionally, the SCCM_Ctrl may contain the identity of values ofspecific orthogonal codes for use with specific sub-channels of a commoncontrol channel structure. Such orthogonal codes may include WalshCodes, CAZAC Codes, Zadoff-Chu codes and the like. Further, the specificcodes may be designated as for use with a pilot channel utilized forsynchronization and as a phase and amplitude reference for demodulation,and other codes designated for use with specific data sub-channelscarrying BPSK modulated data in one example embodiment. Referring toFIG. 5C, Digital Modulator 580C provides a modulated control channelsignal MTx-kl, upon receiving the mentioned configuration informationfrom the SCCM_Ctrl, the SCCM_Data to be transmitted, and the timing fromthe Modem Timing Controller 550C. Either, or both of the DigitalModulator 580C and the Digital Demodulator 560C may be disabledutilizing the SCCM_Ctrl signal.

As mentioned previously, such DSSS and CDMA transmission and receptionapproaches and structures are well known in the art including asutilized in the downlink of IS-95, W-CDMA, CDMA-2000 and the like.Further aspects of such art is disclosed in the previously referencesbook CDMA: Principles of Spread Spectrum Communications, by Andrew J.Viterbi (Addison Wesley Longman, Inc., ISBN: 0-201-63374-1).

An alternative embodiment, not shown, of the SLP 500 of FIG. 5A may beimplemented using in reference to FIGS. 5B and 5C a separate bank ofDigital Modulators 580C arranged from 1 to K each with an output MTx-kand respective inputs SCCM_Ctrl-k and SCCM_Data-k, a separate bank ofDigital Demodulators 560C arranged from 1 to L each with an input DRx-l,an associated Detector/Synchronizer 570C and timing control signals, andrespective outputs SCCM_Ctrl-l and SCCM_Data-l, as well as associatedDRx bypasses, DTx combiners and modified SLP Controller 520B as would beapparent to those skilled in the art.

FIG. 5D is an illustration of an exemplary Advanced Backhaul Services(ABS) compliant signal including an in-band and inline signature signaldeployed within a single channel. The vertical (y) axis of the figurecorresponds to the frequency spectrum, while the horizontal (x) axiscorresponds to time increasing from left to right. The bandwidth of theexemplary ABS signal corresponds to the minimum channel bandwidth forthe ABS services, corresponding to BW_(CH) _(_) _(Min). The bandwidthBW_(CH) _(_) _(Min) corresponds to the allocated channelization of theABS system, in some embodiments to BW_(CH) _(_) _(Min) may also specifythe bandwidth of the signal (5D-10,20,30,40,50) occupying the channel aswell, while in other embodiment the ABS signal may be fixed at aproportion of this bandwidth, while in yet other embodiments the signalbandwidth may not correspond to the minimum channelization bandwidthin-so-far as the non-signature signal bandwidth does not exceed BW_(CH)_(_) _(Min). In specific embodiments, the signature based alert signal(5D-20, 5D-40) is related to the minimum channelization bandwidth toBW_(CH) _(_) _(Min), where the non signature based service signal(5D-10,30,50) may or may not correspond to the minimum channelizationbandwidth BW_(CH) _(_) _(Min). In this context, “in band” indicates thatthe signature based alert signal 5D-20,40 (or a alert signal in general)is transmitted within the same frequencies of operation as the userpayload information signals (5D-10,30,50). Additionally, in the currentembodiment, “in-line” indicates that the user payload signal(5D-10,30,50) and the Alert signals (5D-20,40) are time multiplexedtogether, and transmitted “in-line” with each other. In the currentembodiment, specific conventions or rules are followed so as to allow areceiving station adhering to the ABS system to detect and demodulatethe alerts from another station. Embodiments of the ABS system allow forsuch detection and communication even between ABS compliant devices notengaged to direct communication utilizing the user payload signal(5D-10,30,50), or even able to receive and process such user payloadsignals due to devices being from different manufacturers or havingincompatible configurations in hardware software, or management. Apre-determined arrangement of BW_(CH) _(_) _(Min), and/or other systemparameters allow for even non-compatible equipment to detect and receiveinformation to allow for knowledge relating to the presence andpotentially operating parameters of other information associated withother ABS stations within the propagation range for which interferencemay be a problem. Further, as will be discussed further, such ABScompliant stations in some embodiments may be able to not only detectsuch signatures but also respond with transmissions so as to allow forintercommunications between two ABS compliant stations. Thisintercommunication can then occur even for stations in which it iseither undesirable or even physically impossible to intercommunicateamongst directly using the user payload signal (5D-10,30,50).

In a related embodiment, inline signatures/alerts 5D-20,40 are sent atthe maximum allowable transmission power of the transmitter. In otherembodiments, the alerts (inline signatures 5D-20,40) are transmitted atthe same average transmission power level as the composite ABSinformation signal (5D-10,30,50) it is inline with, during the inlinetransmission period. Other embodiments may provide for the alerttransmission power to be set at a ratio relative to the user informationsignals (5D-10,30,50), or the like.

For some embodiments using inline, in-band communications, timingconstraints related to the transmission of the alert signals arerequired, but may allow flexibility within a pre-defined window. In oneembodiment, it is undesirable to require a fixed periodicity for theinline signature. Such an arrangement may be too rigid for specificembodiments. In such an embodiment, inline transmission periods couldbe:

-   -   i. Shorter than T_(Min) ^(Alert)    -   ii. Longer than T_(Min) ^(Alert),    -   iii. where T_(Max) ^(Alert)=T_(Min) ^(Alert)+T_(VALID) ^(Alert)

Referring again to FIG. 5D, T_(VALID) ^(ALERT) represents the period oftime in which the transmission, or the detection of an alert ispossible. T_(Max) ^(ALERT) represents the maximum duration in time sincethe detection of the last alert (or in other embodiments another timereference or event) that an alert may be received, or expected. T_(Min)^(ALERT) represents the minimum time (e.g. the soonest) for which analert may be expected or allowable to be transmitted since the lastalert (or in other embodiments another time reference or event).T_(Actual) ^(ALERT) represents the actual time between alerts (or inother embodiments another time reference or event). Other “events” mayinclude, but are not limited to, the reception of other signals such asalerts for other ABS compliant systems, or an absolute time reference,GPS time, IEEE1588 time references, or the reception of anothersignature within the ABS compliant transmission signal, which triggerssuch a relationship to an alert reception timing. The various T_(X)^(ALERT) parameters may be coded within ABS devices (or known a priori),or retrieved from the registry server (based upon geographic location orregion for example, or based upon ABS station identification in anotherexample), broadcast by ABS devices, or retrieved from a look up table.Such parameters may be usable, in one embodiment for both inline alertprocessing, but also embedded alert processing, while in anotherembodiment usable for transmission and reception on the common controlchannel—out of band.

FIG. 5E is an illustration of an exemplary Advanced Backhaul Services(ABS) compliant signal including an in-band and inline signature signaldeployed within multiple channels. In this embodiment, an example of anABS compliant system utilizing multiple channel for transmission andreception is depicted.

BW_(Signal) represents the entire bandwidth, or equivalent number ofoccupied minimum channels BK_(CH) _(_) _(Min) in use by a specific ABScompliant system, in one embodiment. In this embodiment, the modulationsymbol rate of the user information signal 5E-10,30,50 will beproportionally faster (by the ratio of BW_Signal/BW_(CH) _(_) _(Min))than that of the alerts (5E-20A-D,5E40A-D). This is because theindividual alert signals (5E-20A-D,5E40A-D) in this embodiment are sentin a manner consistent with those sent for an individual channel asdepicted in FIG. 5D, as alerts 5D-20,40, and each will occupy anindividual bandwidth BW_(CH) _(_) _(Min). In the current embodiment,however, the modulated symbols for the information payload signal5E-10,30, 50 occupy the entire BW_(Signal) and have a proportionallyshortened symbol period in a single-carrier modulation scheme or aproportionally increased number of carriers in a multi-carriermodulation scheme. Other embodiments may utilize individual informationcarrier signals of the same modulation symbol rate as the alerts, andform a multicarrier signal as an alternative, so as to provide aplurality of the signals depicting in FIG. 5D, but in a multiple carrierarrangement of FIG. 5E. In yet other embodiments, a combination ofmulticarrier information signals and individual information signals ofvarying bandwidths may be utilized. In one embodiment, despite one ormore arrangements of signal information bandwidths within BW_(Signal)the bandwidth of the alert signals will be the same or similar as thatdepicted in FIG. 5E. In other embodiments, there may be a set ofpossible alert signal bandwidths.

FIG. 5F is an illustration of an exemplary embodiment of AdvancedBackhaul Services (ABS) signature signals of various structures.Referring to row A, an alert signal 5F-10 is of length L^(ALERT) In theexample embodiment of row B, a single signal 5F-20 is depicted of lengthL^(SIG). In this embodiment, L^(SIG) is equal to L^(ALERT). In theembodiment of row B, the alert signal 5F-20 includes two signature codesequences, one modulated on the in-phase channel (I) and anothermodulated on the quadrature phase channel (Q) of a QPSK modulator, as isknown by one skilled in the art. Such an arrangement allows for the twosequences to be respectively individually modulated by signatureinformation bits S(0), and S(1). The present embodiment can support anumber of different modulations including, for example, coherent BPSK asdescribed herein. In one embodiment, the I code sequence and the Q codesequence are not the same, and allow for detection utilizing individualcorrelators as will be discussed. For example, when S(0) is equal toS(1), the resulting information bit is interpreted as a “0”. On theother hand, when the correlated values of the are opposite sign (forexample, when S(0) results in a positive correlation value, and S(1)results in a negative correlation value) the resulting information bitis interpreted as a “1”. Many other arrangements and variations may beused as well, consistent with coherent modulation techniques. In oneembodiment, the in-phase information bit S(0) may be transmitted as a 1,and treated as a pilot signal or symbol, whereas the quadratureinformation bit S(1) may be interpreted as the payload informationsignal. Other arrangements are possible as well, allowing for othermodulations such as QPSK, and m-ary QAM modulation. The signature codesequences I and Q may be any number of types of codes as known in theindustry and as discussed. In one embodiment, the I and Q codes are twocodes orthogonal to each other, such as may be produced utilizing amaximal length code (m-sequence or m-code), and modulated by twodifferent Walsh codes as in known. In yet further embodiments,alternative orthogonal codes may be used such as so called CAZAC codes,or Zadoff-Chu codes. In yet another alternative embodiment, the I and Qcodes may be multiple codes, each having a plurality of Walsh codes,where one set for I and Q includes a code division multiplexed pilotreference signal with pre-determined values of ones (for example) forthe polarity of both the I and the Q Walsh codes of the pilot channel,and the third and fourth codes are the codes associated with S(i) andS(i+1) for the alert sequence. Of course, the I and Q Walsh codes may bere-used for each of the two I and Q Walsh codes, but with a third Walshcode applied to one of the I/Q sets so as to produce a third and fourthorthogonal code. In the current embodiment, all four Walsh, or otherorthogonal codes may then be “covered” or scrambled on a chip by chipbasis with an alert code, such as m-sequence, gold code, a portion ofthese, or the like.

Alternatives not utilizing orthogonal codes are possible as well, forinstance using two different m-sequences for each of the I code and theQ code where the length of each m-sequence is equal to L^(SIG) andincludes the signature sequence(s). Alternative codes which may beutilized include Barker codes, gold codes, and others and known in theart.

Referring now to the embodiment of row C, two sets of signaturesequences 5F-30A, 5F-30B are sent per one alert time period(L^(SIG)=½*L^(ALERT)) Each signature information bit S(n), where n=0 to3, may be utilized so as to produce a number of different modulationformats including both coherent modulations, and differentially encodedmodulations. Some example modulations utilized in various embodimentsinclude DBPSK and DQPSK using differential encoding; and BPSK, QPSK, QAMutilizing a phase reference such as a pilot bit, pilot symbol or pilotchannel). Various codes and modulation structures may be utilized asdescribed in the foregoing.

Row D of FIG. 5F depicts a similar arrangement as row C, except where Nsets of signature code sequences (5F-40A to 5F-40N) are depictedallowing for 2*N information symbols S to be utilized. The currentembodiment includes code sequences of length

$L^{SIG} = {\frac{1}{N}*{L^{ALERT}.}}$

FIG. 5G is an illustration of an exemplary Advanced Backhaul Services(ABS) compliant signal including an in-band and embedded signaturesignal. The previous figures FIG. 5D, FIG. 5E and FIG. 5F, depicted“inline” alerts as discussed. As an alternative, in band embedded alertsmay be utilized. Similar embedded signaling was first introduced inco-pending application U.S. Ser. No. 13/763,530, the entirety of whichis incorporated herein by reference. The term embedded is used in thecurrent context to describe an alert signal 5G-25, 5G-35 which is nottime multiplexed with the payload information bearing signal 5G-10,5G-30 but is present at the same time as the payload signals duringspecific periods of time. In this embodiment, the transmission 5G-25during a T_(VALID) ^(ALERT) period includes a plurality of individualalert signals 5G-25A through 5G-25H, each of length L^(ALERT) such thattransmission 5G-25 is referred to as a composite embedded alert signal.Likewise, the composite embedded alert signal 5G-35 includes a pluralityof individual alert signals 5G-35A through 5G-35H. The repetition of theidentical individual alert signals making up each composite embeddedalert signal is performed so as to compensate for a reduced transmissionpower level P_(Emb) ^(ALERT) relative to the transmission power levelfor the payload information signal 5G-10,5G-30. The time period in whichalerts may be received, as explained previously, is denoted T_(VALID)^(ALERT) and encompasses the entire composite alert sequence 5G-25, andrespectively 5G-35 in a separate valid period. In the currentembodiment, the information carried within 5G-25 and 5G-35 is different.Within a given composite embedded alert signal, the individual alertsignals are the same and each individual alert signal includes one ormore modulated information bits (such as S(0) through S(2N-1) of FIG.5F.) Thus, the individual information bits within a given compositealert signal remain the same so as to allow further processing such ascoherent combination of the individual alerts 5G-25-A through 5G-25Hwithin composite alert signal 5G-25. Such coherent combinationprocessing results in compensation for the reduction of the transmittedpower level of the alerts relative to the payload information bearingsignal by the amount P_(Emb) ^(ALERT). In one embodiment, N embeddedalert signatures may be transmitted at P_(MAX)−10*log 10(N), or in yetother embodiments, a power level based upon such as calculation. Furtherin such an embodiment, the N embedded signatures may be transmittedsequentially such that coherent combination is possible over T_(VALID)^(Alert).

In order to prevent the combination of individual alerts of differentcomposite alert signals 5G-25 and 5G-35, a gap of time between theT_(VALID) ^(ALERT) periods is defined so as to ensure only individualalert signals of the same composite alert signal are combined together.The spacing between successive T_(VALID) ^(ALERT) periods are defined byT_(Min) ^(ALERT) and T_(Max) ^(ALERT) as previously discussed, anddepicted within FIG. 5G. For both the inline and the embeddedembodiments of the alert signals, the use of a window of time T_(VALID)^(ALERT) for the transmission of alert signals and/or composite alertsignals provides for some flexibility, in some embodiments, as to theexact transmission start time of the alert transmissions allowing forthe alignment of the transmissions so as to be convenient with othersignaling such as a frame timing, start of frame, end of frame,super-frame, or other structure of the payload carrying ABS signalitself. Alternatively such flexibility may allow for the avoidance oftransmitting alert signals at a time when it is not advantageous to theABS payload signal, such as when particularly time sensitive informationis being transmitted, when noise sensitive signals are being transmittedsuch as channel estimation reference signal(s), or other phasereferences, or to avoid the disruption of the payload signal framing,segmentation, or other grouping of the information signals. As a result,in one embodiment, valid alert transmission T_(ALERT) ^(VALID) periodsmust be:

-   -   i. End prior to T_(Max) ^(Alert) from the beginning of the        previous alert transmission.    -   ii. Begin after T_(Min) ^(Alert), from the beginning of the        previous alert transmission.    -   iii. where T_(Max) ^(Alert)=T_(Min) ^(Alert)+T_(VALID) ^(Alert)

In embodiments of an ABS system utilizing embedded signatures, theembedded alert signals will act as noise to the user payload bearingsignal (5G-10,5G-30). In some embodiments, the alerts have a code lengthk providing a “processing gain” resulting from a correlation in areceiver of 10*log 10(k), as previously discussed. If k is sufficientlylarge, the alert signal(s) may be transmitted at a relative power levelreduction P_(Emb) ^(ALERT) such that the interference resulting form theembedded signal is manageable with no further processing. For example,if the modulation for the ABS payload information signal requires 25 dBof signal to noise and interference

$\left( \frac{S}{N + I} \right)$

to be demodulated with a reasonable error rate, an interference level 10to 20 dB below this level (I_(Margin)) would be appropriate. Note thatwithin this discussion the term SNR may be understood to includeinterference as well, and the interference aspect may not be explicitlymentioned in every instance. As a result of the desired SNR for thedemodulation of the ABS information payload signal, within thisembodiment, the power of the alerts would be set to a value below thepayload information signal by P_(Emb) ^(ALERT)=25 dB+I_(Margin). Thisrelationship assumes that the “chip rate” of the alerts, is comparableto the symbol rate (or sample rate) of the ABS information signal withinthe relevant channel bandwidth. In contrast to the SNR considerationsfor the payload information bearing ABS signal, the received alertsignals must also be detected with a sufficient SNR, which is anopposing motivation. In general, for a high probability of detection ofthe signatures, any metric utilized to perform detection should have asignal to noise ratio allowing for an acceptably high probability ofdetection and an acceptably low probability of false detection. Oneapproach to achieving a high probability of detection is to transmit thealerts signals at a higher level, thus impacting the SNR of theinformation-bearing signal. However, the relative transmission power ofthe alert signals in the current embodiment is set by P_(Emb)^(ALERT)=25 dB+I_(Margin).

A discussion of the signal to noise ratios associated with theprobability of detection and false detection may be found in CDMA:Principles of Spread Spectrum Communications, by Andrew J. Viterbi(Addison Wesley Longman, Inc., ISBN: 0-201-63374-1) pages 48 to 52 andelsewhere. In some embodiments, the resulting signal used to determinedetection of the embedded composite alert signals will be the result ofthe correlation of the individual alerts, and then the combination ofthe individual alerts into a signal detection signal, which will be usedfor a detection hypothesis, against a metric. Just as the alertsequences act as noise to the demodulation and successful detection ofthe information symbols of the ABS information signal, the informationsignal will act as noise to the successful detection and demodulation ofalert signals. Therefore, the processing gain (e.g. the length of thealert signature k) must be sufficiently long, in some embodiments, so asto provide an alert detection SNR that allows for an acceptableprobability of detection and a sufficiently low probability of falsealarm, associated with the transmission of the alert signatures P_(Emb)^(ALERT) dB below the information payload signal.

In one embodiment, a detection hypothesis for alert signals is basedupon a ratio of the correlated to uncorrelated energy of the alertsequences. Such a test has the added benefit of reducing falsedetections in the presence of very strong uncorrelated signal levels incontrast to a test based upon correlated energy exceeding a threshold.An example of one such test is based upon the following hypothesis:

Alert detection Det(h), if

$\begin{matrix}{{\frac{1}{N_{MaxAlerts}}*{\sum\limits_{n = 0}^{n = N_{MaxAlerts}}\frac{P_{DET}^{AlertCorr}\left( {h - n} \right)}{P_{DET}^{AlertUncorr}\left( {h - n} \right)}}} > {{TH}_{DET}^{ALERT}.}} & {{{Eq}.\mspace{14mu} 5}\text{-}1}\end{matrix}$

where,

-   -   Receivers must integrate for N_(MaxAlerts), where N_(MaxAlerts)        is equal to the maximum number of alerts which are possible        within the time window T_(VALID) ^(ALERT), and for each h.    -   h is the alert code sequence(s) start time under the current        hypothesis being tested.

The above test allows for the detection of either inline or embeddedalerts with a certain probability P_(Detect) ^(Alert) of detection, anda certain probability of false detection P_(False) _(_) _(Detect)^(Alert). Such a process requires performing the above test over allpossible start times of the alert signal within T_(VALID) ^(ALERT).

While the forgoing discussion includes embodiments for embedded alerts,which balance the transmitted alert signal power with interference tothe ABS information signal, alternative embodiments allowing for ahigher transmission power of the alerts may be utilized which providefor both a higher alert transmission power, and maintaining the SNR ofthe ABS information payload signal at the intended receiver(s), throughthe use of interference cancellation at the intended receivers. Despitesuch an alternative, the detection hypothesis test of Eq. 5-1 may beutilized with interference cancelation at the receiver as well.

Interference cancelation in this context provides for subtracting aknown undesired interfering signal from a total received signal toresult in a remaining signal that has an improved SNR. The use ofembedded alerts is one such situation allowing for the use ofinterference cancelation at a receiver attempting to receive the ABSinformation payload signal because the signature(s) (the exact codes) ofthe alerts are known a priori to the reception of the signal as havingbeen defined as part of the overall system, or communicated as part ofan overhead message of some sort between the transmitter and thereceiver. Further, the power level relationship and likely the phaserelationship between the information signals and the alert signals maybe known as well in some embodiments. In general, each “unknownparameter” such as amplitude, phase, information signal, code sequence,etc., are estimated to allow the generation of an estimated interferingsignal to allow for the actual interfering signal to be cancelledutilizing a subtraction of the estimated interfering signals from thetotal signal where the total signal contains the actual interferingsignal (or signals). The more parameters that are known before hand(such as code sequence, amplitude, phase, and timing) the fewerparameters require estimation, thus reducing the complexity andopportunity for error in an implementation at a receiver. Suchprocessing (an interference canceller) may be implemented in someembodiments after down conversation, digitization, and spatialprocessing, but prior to demodulation of an individual stream. Forexample referring back to FIG. 5A, an alert signature signal cancelationprocessor may be implemented, in one embodiment, within the SignatureLink Processor 500. Utilizing an interference cancelling Signature LinkProcessor embodiment would allow for an increased performance of thedetection of alert signals as the alert signals may be transmitted at alevel relative to the ABS information signal which would not allowsufficient SNR for the demodulation of the ABS signals withoutinterference cancelation in specific embodiments. Further, such anarrangement in embodiments, may allow for an enhanced security between atransmitter and receiver of the same link, providing for knownparameters to be shared for use in the interference cancelation“parameter estimation” process. In such an arrangement, one feature ofenhanced security comes from the fact that the shared parameters may bemodified occasionally, or continuously with such knowledge only beingshared between the transmitter and receivers of a trusted link(s), whichother receivers would require full estimation, and which may provechallenging in specific embodiments. Further, the use of such parametersby a receiver may be used, in specific embodiments, as a form ofauthenticity check to confirm the continual identity of the transmittingstation.

Embodiments of structures for receiving and transmitting alertsignatures, and signals were, in part, described associated with FIGS.5A, 5B, and 5C. Further details, and embodiments of functions associatedwith the Signature Control Channel Detector/Synchronizer 570C and thesignature Control Channel Digital Demodulator 560C of FIG. 5C will nowbe described. Additionally, embodiments capable of detecting anddemodulating either inline or embedded signatures within a singlereceiver structure are also described. Alternative embodiments requiringa dedicated receiver for one or both the inline and the embedded alertsignals are contemplated as well.

In some embodiments where a device must be able to detect both an inlineand an embedded signature signal using a single receiver structure, itis contemplated that the chip rates of the inline and the embedded areto be the same, and only the power level versus repetition number bedifferent. In related embodiments, the detected alert power ideallywould result in the same or a substantially similar level, independentof the alerts being embedded or inline. Such embodiments may allow fordetermining information relating to the received level of the ABSinformation payload signal based upon the detected alert signal level.Such information, in specific embodiments allow for an assessment of thepotential for interference with or from the transmitting ABS station asdiscussed previously.

FIG. 5H is an exemplary block diagram of an embodiment of a SlidingCorrelator (CS). The depicted embodiment of the sliding correlator 5H-10is implemented within a finite impulse response filter (FIR) 5H-20,whose correlated output is effectively the channel impulse response ofthe wireless propagation channel between a transmitted signature and thesliding correlator's associated receive symbol stream from IBR ChannelMUX 328A of FIG. 5A or associated receive chain output from IBR RF 332Aof FIG. 5A. The sliding correlator 5H-10 additionally outputs noise as aresult of correlation with “uncorrelated” inputs such as signal from theABS information payload signals (5D-10, 5D-30, 5D,30 5E-10, 5E-30,5E-50, 5G-10, 5G-30), and uncorrelated interference from othertransmitters, as well as from receiver front end thermal noise sourcesand the like. This input to the sliding correlator may be, in oneembodiment, the DRx-kl of FIG. 5C, and the sliding correlator is withinone or more of blocks 560C, and 570C of FIG. 5C. In the currentembodiment, FIR 5H-20 is a complex FIR, receiving complex input, and FIRfilter coefficients from Code Register/Input 5H-30. To the extent thatthe alert signature code(s) are real valued, the code provided by 5H-30may be real valued as well. For complex values codes such as Zadoff-Chucodes, the code register 5H-30 provides the complex valued code to theFIR filter 5H-30. In one embodiment, a complex code provided by coderegister 5H-30 includes one Walsh code chosen from a set of orthogonalWalsh codes for the real portion of the code input to the FIR 5H-20, andanother Walsh code, different from the first Walsh code but from thesame set of Walsh Codes as the imaginary input to the complex FIR filter5H-20. In another embodiment, two different Barker codes of the samelength are provided to the real and imaginary code inputs. In anotherembodiment, two different m-sequences of the same length, or portions ofa longer code of the same length are provided to the real and imaginarycode inputs. In one embodiment, the output of the sliding correlator5H-10 as described above will provide the complex impulse response ofthe correlated signal transmitted through a wireless channel to thereceiver as modified by the instant multiplexing settings of IBR ChannelMUX 328A of FIG. 5A.

FIG. 5I is an exemplary block diagram of an embodiment of a ComplexSliding Correlator Block (CSCB). In one embodiment, two slidingcorrelators 5H-10A and 5H-10B are used with a single complex valuedinput, but with different codes including a pilot channel based upon ain-phase and quadrature set of Walsh codes (for example, W0 and W1), anda data channel having two other Walsh codes (for example, W2 and W3),wherein the set of Walsh codes is chip by chip covered by a gold code toform Sequence Set j (SSj). Two of the codes within SSj, denoted as S1and S2 (for Pilot I and Q, and respectively including W0 and W1) areprovided to SC 5H-10A, and the the other two codes, denoted as S3 and S4are provided to SC 5H-10B (for the data channel). The complex output ofthe two sliding correlators (SCs) are provided as respective outputs, aswell as respectively squaring them (utilizing blocks 5I-20 and 5I-30) todetermine the magnitude squared of each, which are then summed togetherat 5I-40 for use in the detection hypothesis of Eq. 5-1 (as Maĝ2 oralternatively as Mag via SQRT—square root—block 5I-20). The Maĝ2produced by block 5I-30 provides a value proportional to the power term“P” required by EQ. 5-1. Compensation for the proportionality may bemade by adjusting the TH_(DET) ^(ALERT) value appropriately tocompensate for any impedance value of the Maĝ2 measurement, relative toa value required for an exact power measurement. In alternativeembodiments, for instance, where the S(0) provides the phase referenceand S(1) provides the data values (as described associated with FIG. 5FRow B for example) the code sequence set (SS(j)) is composed of only twocodes, one for each of the two sliding correlators. The slidingcorrelators, in this embodiment are correlating an incoming complexsignal with a single real code (each of which includes two real FIRfilters for performing correlations in this embodiment.)

FIG. 5J is an exemplary block diagram of an embodiment of a SlidingDetector (SD). Sig(n) are time samples of the complex (I and Q) valuesindexed by the variable n of receive signal. In one or more embodiments,Sig(n) are DRx-kl of FIG. 5B and FIG. 5C, where kl may vary from 1 toKL. In some embodiments Sliding Detector 5J-10 includes functionalityincluded within signature Control Channel Modem 510B-kl. In otherembodiments, Sliding Detector 5J-10 is within signature Control ChannelModem 510B-kl.

Sliding Detector 5J-10 includes CSCB 5I-10. The sequence set (SSj) isprovided by the Sliding Detector Control input, which providesadditional control inputs in various embodiments. The Mag and Maĝ2outputs of 5I-10 are provided, in one embodiment, as outputs of SlidingDetector (SD) 5J-10, and as outputs of the CSCB 5I-10. Other embodimentsof a Sliding Detector 5J-10 and/or CSCB 5I-10 may have only one orneither of such outputs, potentially depending upon the embodiment ofdetector/demodulator, such as 5K-00 of FIG. 5K, 5L-00 of FIG. 5L, orSignature Control Channel Modem 510B-1 of FIG. 5B. Other outputs of theCSCB 5I-10 of Sliding Detector 5J-10 include the complex outputXC_Si_A(n), which is a function of the discrete time index n, and iscoupled to conjugate block 5J-40, via in-phase and quadrature (real andimaginary) lines to a complex numerical representation (in the currentembodiment). Such a conversion is often ignored in general block diagramrepresentations, and may be considered inherent in some embodiments, orintegrated with another functional block.

Additionally, in the current embodiment, output XC_Sj_B(n) is providedto complex multiplier 5J-50. In certain embodiments, the conjugatedsignal from 5J-40 represents the phase (mathematically conjugated) ofthe received signal for a pilot CDMA channel derived from a correlationwith the CSCB using one or more orthogonal codes (as described above inone embodiment), and providing for a demodulation of a pilot codechannel. Further, the signal resulting from 5J-30 may represent a dataCDMA channel resulting from the CSCB 5I-10 utilizing one or more otherorthogonal CDMA codes, potentially including one or more “cover” PNscrambling codes (again as described in the foregoing on one or moreembodiments). In such an embodiment, using a CDMA pilot code channel andCDMA data code channel, the de-spread and de-multiplexed informationsymbol SMj(n) is provided as an output of the Sliding Detector 5J-10.

In another embodiment, where a coherent pilot signal is provided to thein-phase portion of the transmit signal (as S(0) of FIG. 5F of Row B forexample), and a modulated (BPSK) symbol is provided to the quadraturesignal during modulation (as S(1) of FIG. 5F of Row B for example) onlythe imaginary portion of the de-spread, and phase re-rotated signal isprovided to the output of the Sliding Detector 5J-10, for furtherprocessing. In another embodiment shown in FIG. 5J, the demodulated andphase de-rotated signal is provided to the Sign function 5J-70 prior tooutput as Dj(n), which may be considered a “slicer” providing for anyvalue greater than or equal to zero as a positive 1 digital output, andany value less then zero as a digital zero output. The configuration ofthe specific codes and associated processing is configured by theSliding Detector Control input.

FIG. 5K is an exemplary block diagram of an embodiment of an inbandinline signature detector, wherein the forgoing embodiments may bedemodulated and detected. The set of signals provided by the SlidingDetector is designated as Vj(n), where n is a discrete time index forthe resulting “convolution” of the FIR filter codes in CodeRegister/Input 5H-30, with the input signal 5K-02, and the associatedprocessing of the various embodiments discussed. In one embodiment, theVj(n)=Dj(n), SMj(n), Magj(n), Maĝ2j(n). Other embodiments may provide asubset, or a superset of the signals included as Vj(n). V(j) is thenpassed as an input to the Detection Logic block 5K-30, where theMagj(n), and/or Maĝ2j(n) is utilized (or even locally derived in someembodiments) so as to perform the detection of the signal, andidentification of the signal or signal multipath components for use withdemodulation. For example, one approach to detection would be todetermine the first signals to exceed a threshold. Another exampleembodiment uses the maximum or “peak” signal above a threshold. A yetfurther embodiment, with more optimal performance, provides for thecoherent integration (simple real values summed, and imaginary valuessummed respectively of SMj(n), or Dj(n) for embodiments where the Sign5J-70 is not performed on the signal) of all values having a magnitudeor Maĝ2 above a threshold. Such an embodiment may be considered anoptimized form of a so-called “rake receiver”, or matched channelfilter. Such an arrangement is advantageous as all the values of SMj(n)which are above a threshold have been de-rotated and aligned in phaseallowing for coherent integration. There are a number of approaches thatare contemplated for detection within the processing of 5K-30 DetectionLogic. In one embodiment, all the values of Vj(n) are stored, andinformation useful for determining the threshold for the current and/orfuture values of Vj(n) (or V_((j+1))(n) for example) are utilized aloneor by interacting with Detector Controller 5K-40. In other embodiments,only a subset of values of Vj(n) are stored and/or values derived fromVj(n) associated with statistics for setting the detection thresholds,and the resulting detection values. Additionally, the demodulation“slicing” of an information symbol resulting from processing of SMj(n)for example may be performed to result in demodulated bit(s) associatedwith M-ary QAM modulation (including BPSK, QPSK, and higher ordermodulation symbols).

In one embodiment, the slicing of the detected modulation symbol is notperformed within 5K-30 but performed in a subsequent block, such asDetector Controller 5K-40 or elsewhere in the IBR.

Coherent demodulation has been described in forgoing embodiments, but invarious embodiments, Detector Controller 5K-40 and/or Detection Logic5K-30 may perform differential demodulation as well, such as DQPSK,DBPSK. For example, the Detection Logic 5K-30 may store symbols fordifferential processing. In yet additional embodiments, a single codemay be used rather than two in some embodiments of differentialmodulations.

FIG. 5L is an exemplary block diagram of an embodiment of an in-banddetector Signature detector useful for either inline or embedded alertsignals using repeated codes as described associated with FIG. 5G andrelated embodiments. The blocks of FIG. 5L are capable of operating inan analogous manner to the blocks of FIG. 5K for inline signatureoperation. For embedded alert signal operation with the repeatedsignature codes (such as depicted in FIG. 5G) the replicated blocks ofFIG. 5K will operate in a similar way in some embodiments. However, forembedded and repeated signatures, a coherent integration of each phasede-rotated symbol will be performed utilizing Vj(n) summed, via summer5L-10, with the contents of Memory 5L-20. Upon initiation of the receivedetection process, Detector Controller 5L-40, in one embodiment, willclear the contents of Memory 5L-20 to all zeros. Alternatively, Summer5L-10 may be controlled so as to not include the output VIntOut(n) 5L-22during a first integration pass effectively adding zeros to the incomingVj(n) values and outputting VSum(n) to be stored in respective memorylocations of Memory 5L-20 indexed by n, and under the address control ofDetector Controller 5L-40. In one embodiment, the Memory 5L-20 is ofsufficient size so as to store all values from the repetition of thesignature, within directly using the summer 5L-10 during real timeprocessing. In alternative embodiments, the phase de-rotated, “matchedfilter outputs” are stored in Memory 5L-20, and iteratively summed withthe previously de-rotated matched filter outputs so as to performcoherent integration on a repeated code by code time scale (as describedassociated with FIG. 5G and for example using repeated codes 5G-25-Athrough 5G-25-H), thereby repeating through the addresses in the memoryonce for each signature repetition as aligned to the beginning of eachcorresponding output of the Sliding Detector 5J-10. In an alternativeembodiment, phase de-rotation by complex multiplier 5J-50 may bebypassed and the CSCB 5I-10 XC_Si_A, and B may be coherently integratedwithin the Memory 5L-20, and phase de-rotation performed afterintegration, by detection logic 5L-30 for example. Additionally, in thevarious embodiments, Detection Logic 5L-30 would perform the Mag or Maĝ2function period to the detection processing and threshold determinationprocessing associated with the discussion relating to embodiments ofDetection Logic 5K-30, and should be considered applicable to thecurrent embodiment. Such processing, in some embodiments, includes thechannel matched filter coherent integration processing associated withthe forgoing discussions. The threshold processing in specificembodiments may be performed utilizing equation Eq. 5-1. Thedetermination of the uncorrelated values may be achieved by summingvalues below a specific threshold from a peak or maximum value, or maybe based upon correlating with a code which is known not to be utilized.In some embodiments, the uncorrelated values may be based upon theoutput of the sliding correlator or related processing for times inwhich the reception of alerts is determined to be unlikely, for examplebetween T_(VALID) ^(ALERT) periods. In yet further embodiments,statistical methods to determine periods without alerts and periodsincluding alerts so as to set a threshold for detection.

The timing of the addressing may be determined and may be adjusted bymonitoring detections performed by the Detection Logic 5L-30 incombination with Detection Controller 5L-40, thereby allowing for thesynchronization and tracking of the T_(VALID) ^(ALERT) periods and theappropriate aligning of the associated times so as to allow for coherentintegration. Further, an intermediate threshold, in some embodiments,may be performed so as to allow for a determination of the currentnumber of alert signature repetitions to include within the coherentintegration, thereby individually detecting each repetition, or a subsetof repetitions. Some embodiments may include a more robust informationfield allowing for the explicit signaling of the number of repeatedsignatures to be determined form the signal itself. In at least oneembodiment, the number of repetitions is known a priori, and in yetother embodiments, the number of repetitions and other informationrelated to the modulation format or timing of transmission is determinedfrom the central registry (4C-60 and/or 4C-70 of FIG. 4C) or anotherdata base (such as Private Database 440, IBMS Private Server 424, IBMSGlobal Server 428, Public Database 452, or Proprietary Database 448 ofFIG. 4G).

FIG. 6A is an illustration of an exemplary Advanced Backhaul Serviceslayered control link communication protocol stack. The figure is dividedinto two vertical columns, denoted by Control Plane and User Plane. TheUser Plane is for use by the IBR and/or the IBMS, in variousembodiments, for the delivery of messages to peer entities (or theirequivalents). One example of the use of the User Plane is interfacing tothe Registry via other ABS devices. In another example, generic IPpackets are passed over the User Plane Protocol. The User Plane's ABSprotocol stack of FIG. 6A begins with the ABS Packet Data ConvergenceProtocol (ABS PDCP). In some embodiments, the operation of the ControlPlane and the User Plan is generally similar from the PDCP layer andbelow with a few exceptions. The ABS PDCP will be discussed below.

The Control Plane is responsible for ABS relegated operation involvingthe procedures and associated messaging required to be compliant withthe ABS Rules as previously discussed, and will be discussed in specificexamples associated with subsequent figures.

ABS-ME (management entity) is the highest portion of the ABS ControlPlane, and is responsible for topology management, processes management,configuration, and interfacing to other ABS peers. The ABS ME interfacesto various “host” radio entities (IBR/IMBS entities in someembodiments), including interfaces to IBR-RLC, IBR-RLP, and even IBR-MACfor timing in some embodiments.

The ABS ME further interfaces to other ABS stack entities as well toperform required functions in some embodiments. In some embodiments theABS ME interfaces to other layers directly, while in other embodimentsassociated sub-layers are called upon to interface to the required ABSstack sub-layer. For example the ABS-ME configures/controls MAC to scanfor interference, in one embodiment directly, and in other embodimentsutilizing the ABS RRC. In the non-limiting subsequent examplediscussion, it will be assumed that each layer interfaces with thelayers directly above or below the layer under discussion. It should benoted that other embodiments may interface in various other ways,including directly between non adjacent layers.

Returning now to the discussion of the ABS ME, example functionsperformed include: configures/controls MAC to broadcast signature,interfaces to IBR IBMS Agent, interfaces to ABS-RRC to send standardizedmessages to other ABS-RRC entities, requests ABS specific proceduresfrom the ABS-RRC, such as so-called—“progressive interference” or“blooming”. These procedures will be discussed in more detail associatedwith subsequent figures.

The ABS Radio Resource Control (RRC) interfaces with the ABS-ME and theABS PDCP to perform services including control/peer messaging, statemanagement, ABS message composition, and interfaces with other ABS-RRCs.

The ABS Packet Data Control Protocol (PDCP) interfaces with the ABS RRCto: arbitrate user plane and control plane priority for access to theABS-RLC, perform “RLC “Framing” by adding a ABS-RLC header, “whitens thepayload” (no 6 sequential 1 s in a row for example), and Ciphering(encryption). The ABS-PDCP Message header addition includes asynchronization field (for example “111111”) and a logical channel indexof 2 bits. The logical channel indication includes (as one exampleembodiment):

-   -   00—EOP (End of Packet)    -   01—ABS RRC (Control Plane)    -   10—ABS UP (User Plane)    -   11—reserved

The ABS Radio Link Protocol (ABS-RLP) interfaces to the ABS-PDCP and theABS-MAC to provide services to the ABS PDCP and higher layers. Functionsperformed by the ABS-RLP include:

Fragmentation into N bit PDUs, where in one embodiment N=1 for inbandand N>1 for out-of-band fragmentation. Other embodiments may provide forinband signaling utilizing N>1 through the use of higher ordermodulation, and/or multiple alert sequences such as embodiments asdescribed associated with FIG. 5F rows C and D.

Forward error correction (FEC)

Cyclic Redundancy Check (CRC)

The ABS Media Access Control (ABS-MAC) interfaces with the ABS-RLP andABS-PHY layers to provide services to the higher layers. The ABS MAC, inspecific embodiments, performs the following example functions:

Transmission/reception timing

Out of band access to the media (listen before talk for out of band)

In-band signaling access to the media

The ABS physical layer (ABS-PHY) interfaces with the ABS MAC to perform(in one embodiment) the following example functions:

Transmission/reception

Modulation/Demodulation using

Interfacing with one or more of channels/formats:

Out of band: Common Control Channel

In-band inline,

In-band embedded

FIG. 6B is an exemplary block diagram of an embodiment of an Advanced

Backhaul Services control link protocol processor. In one embodiment ofthe control link processor, the ABS-MAC is within processor 6B-50, whichinterfaces to various other entities including the IBR RRC, IBR RLC, andIBR MAC to derive timing and coordinate activities. In one embodiment,the ABS-RLP is contained with a separate processor, and an interface toand from the RLP is provided. In alternative embodiments, several or allthe stack functional entities are within Processor 6B-50. In anexemplary embodiment wherein at least the ABS-MAC is contained withinthe Processor, additional functional entities are interfaced, includinga Random Number Generator 6B-20, Clock 6B-30, and one or more timerswithin Timer module 6B-40. The Clock and Timer functions, in variousembodiments, are used to determine transmission timing such as T_(VALID)^(ALERT), and the Alert transmission periods for example, as well asbeing utilized for other functions. The Random Number Generator 6B-20 isused in one embodiment for random transmission time determinationassociated with the common control channel transmission timingprocedure. The ABS-MAC within Processor 6B-50 further interfaces to andfrom one or more Physical Layer entities/MODEMs including in-bandembedded, in-band-inline, and out of band, common control channel.

FIG. 6C is a flow diagram of the MAC receive process for an AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention. During the MAC receive processing, theprocess begins, in the current embodiment, with Step 6C-10 waiting forthe PHY to detect a first alert signature.

Once the first detection has occurred, the timing variables are set inInitialize step 6C-20. In some embodiments, one or more of the variablesmay be set during initial system configuration as well. In the currentembodiment, these variables include in the current embodiment T_(Max)^(Alert), T_(Actual) ^(Alert), T_(Min) ^(Alert), T_(VALID) ^(Alert).Next, the MAC link processor waits for T_(Min) ^(Alert), in Step 6C-30,and then begins waiting for the next PHY indication of a subsequentvalid detection in Step 6C-40. If no symbol is detected within T_(VALID)^(Alert), (step 6C-50) then processing proceeds to step 6C-70 where thehigher layer RLP is notified and reset. Such an occurrence may happen issignal is lost, of if the end of the current RLP frame is received.Alternatively, if an alert is detected for the specified peer MAC (asdetermined in the current embodiment by a property of the alert code set(SSj) such as a secondary orthogonal code for example), the appropriatetimer values are adjusted and processing returns to step 6C-30 (the waitfor T_(Min) ^(Alert) step). In the current embodiment, various alertsmay be received, and for each alert signature which is distinguishablefrom those from other ABS-MACs, a separate ABS-MAC receive process maybe instantiated, along with individual timer values.

FIG. 6D is a flow diagram of the MAC transmit process for a AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention. The MAC transmit process begins in step6D-10 where a MAC service data unit (SDU) is received. The SDU may be asingle bit wherein the modulation is BPSK and the segmentation size isn=1. Alternatively, the segmentation size may be 2 bits, and themodulation may be QPSK. As is known by one or ordinary skill in the art,higher order modulations such as m-ary QAM, and discussed above may beused as well. Once a specific SDU is received by the MAC, permission totransmit may be requested for inline transmissions associated with step6D-20, so as to coordinate with the transmission of the IBR symbols intime. In step 6D-30 if the SDU indicates that a first SDU indication ispresent, a clear channel assessment (CCA) will be performed in someembodiments (for example when transmitting on the common control channelin one embodiment, though not limited to such an embodiments). In step6D-50, the timers are initialized, and processing proceeds to 6D-60.Alternatively if there is not first SDU indication, in step 6D-30, step6D-40 is performed wherein the process waits for T_(VALID) ^(ALERT) tobe come valid, for example by comparing a timer or a clock value indifferent embodiments to the valid time frame T_(VALID) ^(ALERT).

Processing then proceeds to step 6D-60 wherein the MAC waits for anindication from the RRC (in control of the fine scale timing in thecurrent embodiment) to indicate authorization to transmit, if suchauthorization is required (associated with specific embodiments). Next,decision step 6D-70 directs processing based upon T_(VALID) ^(ALERT)being valid. If expiration has occurred, an indication to the RLP isperformed wherein a failure is signaled in step 6D-80. Alternatively ifT_(VALID) ^(ALERT) remains valid, processing proceeds to step 6D-90wherein the MAC PDU is transmitted. The format of the MAC PDU in someembodiments is a simple pass through to the PHY. In other embodiments aMAC header, or other information may be added to the MAC SDU prior tothe MAC PDU being provided to the PHY. Finally, successful transmissionis indicated to the RLP, and the process is exited in step 6D-100.

FIG. 6E is an illustration of the radio link protocol (RLP) messageformat of Advanced Backhaul Services control link control link accordingto one embodiment of the invention. As previously described in specificembodiments, the RLP receives a service data unit (SDU) from the ABSPacket Data Control Protocol (PDCP), including fields 6E-30 (LogicalChannel) at least, and in some instances 6E-45 (the length of theremaining PDCP payload), 6E-50 (the destination address to which thepacket is to be sent), 6E-60 (a variable length RRC message), and 6E-70(a variable length user plane message from higher layers of an IBR forexample. Other embodiments may also include the Sending MAC address6E-20. In other embodiments, the MAC address may be added within the RLPlayer or another layer.

The RLP then next adds the Sync field 6E-10, the CRC field 6E-40, andperforms FEC processing adding tail bits 6E-80. The result is passed tothe MAC as a RLP PDU/MAC SDU.

FIG. 7A is a flow diagram of the RRC transmit process for a AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention. When the RRC has information to transmit toa peer, or to broadcast alerts in general, the process begins in step7A-10 wherein the ABS RRC receives a command from the Management Entity(ME) to transmit periodic alerts for example. In step 7A-20, the RRCperforms configuration of the various layers so as to transmit periodicalerts such as, in one example, setting the timer values, modulationformats, number of alert code sequences per alert signal transmission,RLP segmentation bits (n), and other associated parameters. In step7A-30, the RRC composes a message (PDU) for the PDCP layer and requeststhe transmission of an alert (7A-40). Next in the current exemplaryembodiment, the RRC waits for T_(MIN) ^(ALERT), and then returns to step7A-40 to transmit another alert.

FIG. 7B is a flow diagram of the RRC scan process for a AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention. In the embodiment of FIG. 7B, the MErequests the RRC perform a scan function (step 7B-10). The RRC thenconfigures the appropriate layers using pre-determined informationstored within the ABS system, or determined form received informationform a registry for example in one embodiment. Other embodiments mayreceive information form the IBR or IBMS, or another source (step7B-20). The specific parameters to be configured vary in differentembodiments, but may include those described associated with step 7A-20and elsewhere. In step 7B-30, the RRC requests a scan from the ABS MACfor a specific duration TSCAN, and on a list of channels defined byCH_(SCAN). Finally, the RRC receives a report for each scan from theMAC, and once complete, reports the result to the ME in step 7B-40.

FIG. 7C is a flow diagram of the RRC Bloom process for an AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention. The ABS RRC, in one embodiment, receives arequest form the ME requesting the “Bloom” process (step 7C-10). Someembodiments the process includes entering the Bloom process registerwith the registry that it is entering the Bloom process. Otherembodiments include the requirement, or option for the stationperforming the Bloom process to notify one or more stations which mayreceive interfering transmission of the state of entering the Bloomprocess, and optionally update such stations of that process.

Embodiments of the Bloom process include incrementally “progressiveinterference”, so as to initially have a lower impact in terms ofinterference to any existing ABS devices which happen to be with thepropagation range of a new ABS device being brought up for operation.For example, a Tier 2 device being brought up in the vicinity of a Tier1 Incumbent device with settings in the registry allowing for otherdevices to operate in the region but with limitations so as to notinterfere with the T1-I device require, in one embodiment, a Bloomprocess. In fact, in some embodiments, any device having a lower tier,or same tier and having a lower priority or right to operate in thevicinity of other devices either as reported by a registry, or detecteddirectly in some cases use a Bloom process. Such a process allows forthe higher tier, or priority device (one having been operating in thearea longer but of the same tier) an opportunity to detect interferingtransmissions from a device performing a Bloom process. Such a processallows the level of interference to be detectable, but not necessarilycatastrophic to the link of the existing devices. Step 7C-20 providesfor the RRC to configure the Bloom process, defining in one embodiment avariable “Step” with a value of 0, initially. Additionally the otherlayers of the ABS stack are configured as well. Next, in step 7C-30, theRRC initiates the ABS Bloom process utilizing parameters TXPower(n), andDutyCycle(n), where n is the step in the progressive Bloom process.After each step in the process, as the process returns to step 7C-30,the setting will be retained for a period of time referred to as Dwell.The process stays in 7C-40 until the Dwell process for Step n hasexpired. In one embodiment, the transmit power will be the full Tx powerexpected for operation of the link, and the duty cycle as determined byDutyCycle(n) for each step n of the Bloom process, will be varied inincreasing percentages of a pre-determined repetition time for the Dwelltime, which may be varies as well on a per Bloom step process. In otherembodiments, both the transmission power and the duty cycle will bevaried progressively. In yet further embodiments, only the power will bevaried, for a given duty cycle, or in any linear, or non-linearcombination. In one embodiment of the Bloom process, only the basicalert signature is sent with no identifying information. In anotherembodiment, the alert signature is sent with a code unique, or anotherproperty unique to station in the Bloom process. In yet furtherembodiments, the Bloom process includes the identity of the transmittingstation in the transmissions, and potentially additional information.

During the dwell process, prior to the expiration of the Dwell timer, orcounter, the ABS station monitors communications channels (in variousembodiments one or more of the common control channel, the inbandcontrol channel, or another out of band link) in step 7C-40 for any“direct messages” from another station notifying the Blooming ABSstation of detected interference. Additionally, in step 7C-50 theBlooming ABS station checks the registry periodically for notificationof detected interference due to the Bloom process. If either stepreceives an indication of detected interference, the process proceeds tostep 7C-80 and the process (and the transmissions) are terminated in oneembodiment. Note that in some embodiments, the process may be begunagain, with adjusted transmission parameters so as to minimizeinterference to the station that detected the Bloom interference. Insome embodiments, the indication of interference from another ABSstation will include information usable to aid the Blooming station toavoid interfering with the detecting station with higher priority(either higher tier, or more seniority for example). Examples of thetype of information usable to set interfere avoiding transmissionsettings were discussed previously in this disclosure associated withFIGS. 4C, 4D, 4E, 4F, and 4G, and elsewhere. Additionally similarprocessing was discussed in co-pending application U.S. Ser. No.13/371,346, the entirety of which is incorporated herein by reference.Note that based upon initial scans, prior to beginning the Bloomprocess, such interference avoiding techniques may be utilized basedupon channel modeling and interference prediction techniques prior tobeginning the transmission process in step 7C-30, or configured in step7C-20. Such a step may also take input from any direct messages receivedrelated to detected interference or similar information receiving in theregistry (4C-60/4C-70 for example) as a result of previous attempts atthe Bloom process.

Returning now to step 7C-40, once the Dwell time has expired, and nointerference indication has been detected, the Bloom process Step isincremented in 7C-60, and processing proceeds to step 7C-70. If the Stepis the Final Step, the process is terminated in 7C-80, otherwise theprocess continues with new transmission settings in step 7C-30.

Further details of the “bring up” of an ABS station, and the associatedmanagement of the Bloom process will be discussed associated with FIG.8C.

FIG. 8A is an illustration of exemplary ABS registry entries accordingto one embodiment of the invention. Parameters associated with entriesin the various embodiments of the registry 4C-60 are discussed in manylocations in this disclose.

The table includes example registry entries for several different tiersof stations operating under the proposed ABS rules. The first columndefines possible entries for one aspect of one embodiment of theregistry. The FCC ID is typical of devices registered with the FCC, andis also required as noted with the white spaces rules.

The MAC Address is a 48-bit IEEE assigned address which can be used toidentify a station from transmissions in one embodiment.

Lat, and Long provide the geographic latitude and longitude of thelocation of the ABS transmitter station.

In addition to Lat/Long, the Address may be entered as well and may bemandatory for a fixed station in some embodiments.

The Tier entry defines the class of service the ABS station is operatingunder as define in forgoing sections.

Tx Power defines the transmitter power of the ABS station. In someembodiments, it is the maximum allowable transmit power, while otherembodiments include the actual transmitter power, or transmitter powerthe station is capable of transmitting.

Antenna Type indicates the type of antenna. For Tier 1 devices, this ismore likely a fixed dish type antenna similar to entries for FCC Part101 licenses. The Azimuth (Deg) and Elevation (m) relate to the antennadirectivity and center pointing direction of a fixed antenna. Furtherexamples include, but are not limited to azimuth beamwidth, elevationbeamwidth (in degrees, not m), polarization, antenna height, azimuthaland elevation bearings at center of the pattern, etc. For devices ofother tiers, or potentially for Tier 1 incumbent devices is some cases,the antenna type may further include whether the antenna is an antennaarray, and any associated array attributes such as the array geometry(number of elements, and their relative geometric position), the numberof receiver and/or transmitter elements, array capabilities such asreceiver and transmitter null steering capacities, and the like.

Equipment ID is the FCC certification ID of the equipment being used andhaving been certified under ABS rules.

“Using Common Control Channel” is an entry for defining which commoncontrol channel, if any, a particular station is utilizing.

M-ACTUAL, M-TOT, M-REG, and Registered Channels (1 . . . M-REG) asdiscussed previously relate to the allowable and in use channels foroperation under the ABS rules.

Duplexing Mode defines time division, frequency division, or so calledzero division duplexing methods (or other such methods as may becomeapplicable).

Licensed C/I (dB) is an entry of an embodiment in which the fees paid,and/or the license received (Tier 2 in one embodiment) defines a C/I forwhich the station receives interference protection assuming it is thehighest tier, and has the seniority in that location. Further detailwill be provided relating to “cooperative” interference mitigation andthe Bloom process associated with the ME in FIG. 8C.

The SIP Address entry is an example address in some tiered serviceradios by which a station may be contacted with a so-called directmessage. For example, in a Blooming process when notification that theBlooming station is causing interference to another protected ABSdevice, a directed SIP message is sent to the Blooming station in oneembodiment.

The P-MAX (dBm), P-NOM (dBm), P-Allow (dBm) are associated with thecooperative interference process for non-Tier 1 devices, and in oneexemplary embodiment, are discussed in more detail elsewhere.

The Date Occupied (or optionally also Time Occupied) and Date Licensedfields are related to determining seniority between ABS stations of thesame tier. The Geographic Region field defines the specific region inwhich a device is operating. Geographic regions were discussed in moredetail relating to FIG. 4D.

FIG. 8B is a flow diagram of the Common Control Channel basic broadcastalert process for an Advanced Backhaul Services control link protocolprocessor according to one embodiment of the invention. In step 8B-10,the ABS ME requests the ABS RRC broadcast a basic Alert. In step 8B-20the ABS RRC requests the ABS PDCP to transmit on logical channel (LC)00, indicating a “basic alert”, which may also, in some embodiment beinterpreted as an “end of packet”. In this embodiment, it is transmittedon common control channel 33. In other embodiments, the transmissionsare transmitted in band as well, or in place of the common controlchannel transmissions. The process waits in step 8B-30 for the alertperiod to expire (T_(MIN) ^(ALERT) in some embodiments). Once the periodhas expired, processing returns to step 8B0-20, and continues.

FIG. 8C is a flow diagram of the Management Entity (ME) Tier 2 channelselection and link initialization process for a Advanced BackhaulServices control link protocol processor according to one embodiment ofthe invention. FIG. 8D is a flow diagram of the Management Entity (ME)Tier 3 channel selection and link initialization process for a AdvancedBackhaul Services control link protocol processor according to oneembodiment of the invention. FIG. 8D is, in some embodiments, a verysimilar process to that of FIG. 8C and can be assumed to be the same,with exceptions as noted in the figure.

Referring now to Step 8C-10 the ME of the ABS device, checks theregistry for any T1 (Tier 1) or T2 (Tier 2) devices in the localproximity for which in must consider interference and previousdiscussed. Of course for a Tier 3 device, other T3 devices are alsochecked in the registry as well (see step 8D-10). In step 8C-20 the MEdetermines channels not in T1 exclusion zones or currently used as T2Channels. For T3 devices, other T3 devices must be considered as well.In step 8C-30 if no unused channels are available, step 8C-40 isperformed, otherwise processing proceeds to step 8C-140. In step 8C-140,when clear channels are determined to be available, the ME configuresthe radio entities (layers), and registers the current configuration ofthe ABS station with the registry. The ME then begins broadcastingalerts, and notifies (in some embodiments) the IBR IBMS, which beginstransmission to peer point to point radios or point to multipoint radiosfor payload traffic. The ME additionally begins to monitor the Registryand/or control channels for interference messages or any directmessages.

If no “clear” channels are available, step 8C-40 is performed and the MEdetermines from the Registry, which channels are candidates for use, soas to avoid or minimize interference to other T2 stations in the currentembodiment. In step 8C-50, the ME requests ABS RRC to perform a scan ofcandidate channels for operation so as to assess the interferencepotential of using these channels. Processing then proceeds to step8C-60, where the ME determines the best candidate channels for operationbased upon scan results and registry information. Such a determinationwill, in some embodiments, involve propagation modeling and interferencemitigation techniques as discussed. The Bloom process is then begun instep 8C-70. ME begins “Bloom Process” and monitors the Registry andin-band and out-of-band channels for direct messages. The decision as towhether direct messages are received or not is performed in step 8C-90.If no direct messages are received, the registry is checked forinterference notifications in step 8C-130. If no interferencenotification is received, the processing proceeds to step 8C-140 aspreviously discussed. Returning to step 8C-90, if a direct message isreceived, step 8C-100 is performed where the ME will stop transmissionand perform an interference mitigation process in one embodiment. Suchan interference mitigation process, in some embodiments, includesresponding to the “interfered with” station via direct message tonegotiate cooperative interference mitigation interaction andmeasurements. Such mitigation may also include adjustments and “trial”test transmissions with iterative feedback from the partner“interference mitigation” station. If the interference is resolvable(8C-110) the processing proceeds to 8C-80 where the radio is configuredwith the determined radio parameters to avoid interference, andoperation returns to 8C-90.

If the interference is not resolvable in step 8C-110, processingproceeds to step 8C-120 and transmission is halted and alternativechannels are selected, and the process is restarted at step 8C-60.

The “Bloom process” as discussed allows for progressive interferencewithout initially being catastrophic to the station being interfered. Inone embodiment, the process is a time division process wherein less than100% transmit duty cycle is employed. For example, the Blooming ABSstation may start at 10% and proceed to 20% and so on in the currentembodiment. This is less damaging, and should not “shut off” the victimstation. In one embodiment, if at any point the Blooming stationreceives a direct message indicating unacceptable interference, then thelower tier or lower priority Blooming ABS station has to cease anddesist if requested to do so. The stations performing the Bloom processmust be certified, as do the stations indicating they are beinginterfered to allow for the transmission of messages ordering anotherstation to vacate certain channels.

In one embodiment, using the Registry, the registry control andarbitration processes between stations serves to order interferingstations to vacate certain channels. The registry time stampsregistration so as to document the specific chronology of the ABSstations in a geographic area and can determine “priority” for same tierdevices so as to arbitrate disputes and enforce rules. A station maysend an “interference notification” message when interfered with, whichis valid only if that station has been in the location earlier than theblooming stations. To ensure this process is legitimate, the Registry,as mentioned, can act as a policy arbitrator and enforcer based on thetime of registration of the individual stations, or as a general processfollowing procedural rules and steps. In some embodiments, there may bea requirement to accommodate others reasonably and work with them viathe “cooperative interference mitigation process”. Such a requirementmay be conditional based on the tiers of the stations, or the density ofthe stations within the area. For example, if one station canaccommodate another station without affecting the performance of theirlink, they may be required to do so, or report that they cannot makeadjustments. In some embodiments, the Registry may provide a benefit tothat station in making accommodations for other stations in termsallowing more capability or an increase in the priority registration,for example.

In one embodiment the station notifying another station of harmfulinterference has the obligation to inform the interfering station of thelevel of interference and potentially other helpful information so as toaid in the reduction of interference and to verify that the interferingstation is the correct one or that the message is not fraudulent, forexample. Such an indication may be considered a “hint” as to how much ofa change needs to be made, or if resolution is possible at all. Suchinformation may include the frequencies the interference is occurringon, and the level of the interference as two examples. Other embodimentsmay include the channel state information or angle of arrival of theinterfering signal.

In another embodiment, where an interfering station is being evictedfrom the currently Blooming or operating frequencies, the station mustbe given a interference mitigation time to resolve the interference interms of adjustment of RF parameters as discussed. In one embodiment, a“notice message” or interference notification includes the specificoverlapping channels, and by the specific amount of power. Themitigation may be considered a “cure time” from the first notice. Upon asecond notice the station, in one embodiment, turns off transmissionsimmediately, unless a cooperative interference mitigation process isdeemed to be ongoing.

An example of such a cooperative interference mitigation processfollows:

1) When an ABS station detects another is interfering, it may invoke theeviction process.

2) The “interfering” station has 1 second to “cure” and must be informedby how much the interference must be reduced.

3) If direct messaging is implemented, one set of rules apply, if a“mail box” approach using the Registry is performed a second set ofrules are utilized, which are less interactive and cooperative (in thecurrent embodiment). Such a process is designed to “align interests”.

4) If there is a direct message, and notice, but not response from theinterfering station, they are required to immediately terminatetransmissions (which may be based upon the registry mail boxnotification process).

5) If there is notice to an interfering station via a direct message,and the interfering station responds, then that station will get anopportunity to fix the interference by adjusting RF parameters. Forexample, if a station wants to have the opportunity to stay and attemptto adapt, it must send a response to the registry in one embodiment, ordirectly to the notifying station (in the current embodiment).

6) If a notified ABS station estimates that it can cure the interferenceproblem, and makes adjustment but does not respond to the notifyingstation, then if such adjustment has resolved the issue, no terminationoccurs as the secondary notice will not occur.

7) However, if a notified station does not respond, and attempts to fixthe issue unsuccessfully, and receives a secondary interferencenotification it must cease transmission immediately in the currentembodiment.

8) If a station does respond to the first direct interferencenotification, that station will receive multiple opportunities toresolve the interference cooperatively.

In some embodiments, the registry may need be to monitored and documentthe process so as to allow for review at a later time, allowing for anappeal process with a supervisory authority such as the FCC. If therules are not followed, the registry may indicate directives to thestations up to and including revoking licenses, or adjusting “occupied”priority status.

In one embodiment, when a dedicated “Bloom” signal is detected (forexample with a unique signature and no user payload), the detecting ABSstation may look in the registry to determine which other stations arein the area and in the Bloom process so as to either determine identityor confirm identity. Such an embodiment requires that the “state” of astation be updated within the Registry.

In some embodiments, the “interfered with” ABS station judges aninterference threshold based upon one or more of: BER impact, C/Iimpact, the power density of the interferer.

In one embodiment, licenses are paid for by station owners based uponthe licensed “Carrier to Interference ratio” (C/I) that is desired orrequired at that location. Having licensed a specific C/I, and wheninterference impinges upon them damaging the C/I beyond the level oftheir license, there are several embodiments operable to resolve theproblem. First, and most simply, the forgoing notification proceduresmay be followed. Secondly, in another related embodiment, a registeredstation gets a fixed amount of protection, and based upon theinterference level being received, the licensed ABS station is allowedto increase its transmitter power by the amount of licensed C/Idegradation that are currently receiving. For example, if you purchase alicense, for 40 dB C/I, you are guaranteed 40 dBi or the maximum yourequipment can do, up to the permissible transmission power limit in theband. In such an embodiment, a licensed station only transmits as muchpower as required for the target receiver to achieve the maximum C/I itcan operate at, above the noise floor plus a nominal margin amount insome embodiments. Notification may only be provided, in the currentembodiment, once a licensed station reaches a “conditional maximum”. Theconditional maximum is the lower of the amount that that you areinterfering with someone else, or all you can transmit.

In related embodiments, the C/I protection affects the license cost. Forexample, it might cost $1K for a 20 dB T2 license, or $2K for 25 dB T2protection license, and so forth.

In one embodiment, the allowable transmit power follows the equation:

P _(Allow)=min(P _(MAX) ,P _(INTFERENCE) ,P _(R,C/I))  EQ. 8-1

For example, if interference encroaches within the C/I you havepurchased, the licensed station may increase its power to regain thelicensed C/I. If the licensed ABS station has increased its power up toeither P_(MAX) or P_(INTERFERENCE), then the offending (interfering)station may be notified to cease, or to follow the interferencemitigation process described previously in various embodiments.

In one embodiment, if the owner of a device wants 45 dB C/I, then theyneed to pay more money to get cleaner spectrum. Associated with suchrules they may be an occupancy requirement to retain the rights, as wellas a requirement that no license may exceed the certified capability ofC/I performance of the equipment being utilized for a given license. Inone embodiment, one cannot purchase more protection than one's equipmentcan actually use. In another embodiment, the “notification” message mustinclude, and the equipment generating the message must be able tomeasure the interference level at a C/I level and accuracy to which thenotification indicates.

In a related embodiment, any device owner may purchase what every C/Ilevel they want, but if the device cannot measure a specific C/I withsufficient accuracy, then it is not within the rules to notify aninterferer of a level of C/I and as a result such a C/I is notenforceable by that equipment. Such equipment must, in specificembodiments, be certified that it can perform the specific measurements.

In one embodiment, the interference notification message is limited to afixed interference back off step, such as 5 dB. If such a back off bythe offending station does not cure the interference problem, anothermessage may be sent.

One or more of the methodologies or functions described herein may beembodied in a computer-readable medium on which is stored one or moresets of instructions (e.g., software). The software may reside,completely or at least partially, within memory and/or within aprocessor during execution thereof. The software may further betransmitted or received over a network.

The term “computer-readable medium” should be taken to include a singlemedium or multiple media that store the one or more sets ofinstructions. The term “computer-readable medium” shall also be taken toinclude any medium that is capable of storing, encoding or carrying aset of instructions for execution by a machine and that cause a machineto perform any one or more of the methodologies of the presentinvention. The term “computer-readable medium” shall accordingly betaken to include, but not be limited to, solid-state memories, andoptical and magnetic media.

Embodiments of the invention have been described through functionalmodules at times, which are defined by executable instructions recordedon computer readable media which cause a computer, microprocessors orchipsets to perform method steps when executed. The modules have beensegregated by function for the sake of clarity. However, it should beunderstood that the modules need not correspond to discreet blocks ofcode and the described functions can be carried out by the execution ofvarious code portions stored on various media and executed at varioustimes.

It should be understood that processes and techniques described hereinare not inherently related to any particular apparatus and may beimplemented by any suitable combination of components. Further, varioustypes of general purpose devices may be used in accordance with theteachings described herein. It may also prove advantageous to constructspecialized apparatus to perform the method steps described herein. Theinvention has been described in relation to particular examples, whichare intended in all respects to be illustrative rather than restrictive.Those skilled in the art will appreciate that many differentcombinations of hardware, software, and firmware will be suitable forpracticing the present invention. Various aspects and/or components ofthe described embodiments may be used singly or in any combination. Itis intended that the specification and examples be considered asexemplary only, with a true scope and spirit of the invention beingindicated by the claims.

What is claimed is:
 1. A first tiered service radio for operating in aradio frequency band according to rules for operation allowing forradios of multiple tiers of service, comprising: a plurality of receiveRF chains; one or more transmit RF chains; an antenna array comprising aplurality of directive gain antenna elements, wherein each directivegain antenna element is couplable to at least one receive RF or transmitRF chain; and an interface bridge configured to couple the radio to adata network, wherein the tiered service radio is configured to performeach of the following: communicate with a network based registry todetermine registry information associated with any registered radiosmeeting specific criteria, wherein the specific criteria includes atleast information associated with at least higher priority tieredservice radio devices to that of the first tiered service radio; scanone or more radio frequency channels for the presence of signature radiosignals transmitted from one or more other tiered service radios togenerate scan data, and wherein the radio comprises at least oneadjustable network parameter that is adjustable based on the scan data,wherein said scanned one or more radio frequency channels are selectedbased upon said registry information, and wherein the at least onenetwork parameter is adjusted to reduce a potential of interference ofthe first tiered service radio with the other tiered service radios orsaid registered radios, wherein the adjusting the at least one networkparameter comprises one or more of: selecting a frequency channelutilized between the first tiered service radio and a second tieredservice radio; adjusting the effective radiation pattern of the firsttiered service radio; selecting one or more of the plurality ofdirective gain antenna elements; and adjusting the physicalconfiguration or arrangement of the one or more of the plurality ofdirective gain antenna elements.